Con un enfoque paternalista Ubuntu de entrada no da acceso a la cuenta de root, sino que los comandos privilegiados se deben ejecutar usando sudo. Since most Ubuntu documentation asks you to use sudo even with graphical applications, Why recommend gksudo or kdesudo for graphical applications instead of sudo. For example, a lot of guides […]
Con un enfoque paternalista Ubuntu de entrada no da acceso a la cuenta de root, sino que los comandos privilegiados se deben ejecutar usando sudo. Since most Ubuntu documentation asks you to use sudo even with graphical applications, Why recommendgksudo or kdesudo for graphical applications instead of sudo.
For example, a lot of guides (including the first book ever published about Ubuntu) will ask you to type this sort of command:
sudo gedit /etc/apt/sources.list
I will always recommend, however, that people use instead this sort of command:
gksudo gedit /etc/apt/sources.list
And reserve sudo for command-line applications, like so:
sudo nano /etc/apt/sources.list
Why is it an issue?
Well, to be perfectly honest, most of the time it isn’t. For a lot of applications, you can run them the improper way—using sudo for graphical applications and see no adverse side effects.
Lisp (historically, LISP) is a family of computer programming languages with a long history and a distinctive, fully parenthesized Polish prefix notation.[1] Originally specified in 1958, Lisp is the second-oldest high-level programming language in widespread use today; only Fortran is older (by one year). Like Fortran, Lisp has changed a great deal since its early […]
Lisp (historically,LISP) is a family of computerprogramming languages with a long history and a distinctive, fully parenthesized Polish prefix notation.[1] Originally specified in 1958, Lisp is the second-oldest high-level programming language in widespread use today; only Fortran is older (by one year). Like Fortran, Lisp has changed a great deal since its early days, and a number of dialects have existed over its history. Today, the most widely known general-purpose Lisp dialects are Common Lisp and Scheme.
The name LISP derives from “LISt Processing”. Linked lists are one of Lisp language’s major data structures, and Lisp source code is itself made up of lists. As a result, Lisp programs can manipulate source code as a data structure, giving rise to the macro systems that allow programmers to create new syntax or even new domain-specific languages embedded in Lisp.
The interchangeability of code and data also gives Lisp its instantly recognizable syntax. All program code is written as s-expressions, or parenthesized lists. A function call or syntactic form is written as a list with the function or operator’s name first, and the arguments following; for instance, a function f that takes three arguments might be called using (f arg1 arg2 arg3).
Lisp was invented by John McCarthy in 1958 while he was at the Massachusetts Institute of Technology (MIT). McCarthy published its design in a paper in Communications of the ACM in 1960, entitled “Recursive Functions of Symbolic Expressions and Their Computation by Machine, Part I”[3] (“Part II” was never published). He showed that with a few simple operators and a notation for functions, one can build a Turing-complete language for algorithms.
Information Processing Language was the first AI language, from 1955 or 1956, and already included many of the concepts, such as list-processing and recursion, which came to be used in Lisp.
McCarthy’s original notation used bracketed “M-expressions” that would be translated into S-expressions. As an example, the M-expression car[cons[A,B]] is equivalent to the S-expression (car (cons A B)). Once Lisp was implemented, programmers rapidly chose to use S-expressions, and M-expressions were abandoned. M-expressions surfaced again with short-lived attempts of MLISP[4] by Horace Enea and CGOL by Vaughan Pratt.
After having declined somewhat in the 1990s, Lisp has recently experienced a resurgence of interest. Most new activity is focused around open source implementations of Common Lisp, and includes the development of new portable libraries and applications. A new print edition of Practical Common Lisp by Peter Seibel, a tutorial for new Lisp programmers, was published in 2005.[20]
Many new Lisp programmers were inspired by writers such as Paul Graham and Eric S. Raymond to pursue a language others considered antiquated. New Lisp programmers often describe the language as an eye-opening experience and claim to be substantially more productive than in other languages.[21] This increase in awareness may be contrasted to the “AI winter” and Lisp’s brief gain in the mid-1990s.[22]
Dan Weinreb lists in his survey of Common Lisp implementations[23] eleven actively maintained Common Lisp implementations. Scieneer Common Lisp is a new commercial implementation forked from CMUCL with a first release in 2002.
The open source community has created new supporting infrastructure: CLiki is a wiki that collects Common Lisp related information, the Common Lisp directory lists resources, #lisp is a popular IRC channel (with support by a Lisp-written Bot), lisppaste supports the sharing and commenting of code snippets, Planet Lisp collects the contents of various Lisp-related blogs, on LispForum users discuss Lisp topics, Lispjobs is a service for announcing job offers and there is a weekly news service, Weekly Lisp News. Common-lisp.net is a hosting site for open source Common Lisp projects.
50 years of Lisp (1958–2008) has been celebrated at LISP50@OOPSLA.[24] There are regular local user meetings in Boston, Vancouver, and Hamburg. Other events include the European Common Lisp Meeting, the European Lisp Symposium and an International Lisp Conference.
The Scheme community actively maintains over twenty implementations. Several significant new implementations (Chicken, Gambit, Gauche, Ikarus, Larceny, Ypsilon) have been developed in the last few years. The Revised5 Report on the Algorithmic Language Scheme[25] standard of Scheme was widely accepted in the Scheme community. The Scheme Requests for Implementation process has created a lot of quasi standard libraries and extensions for Scheme. User communities of individual Scheme implementations continue to grow. A new language standardization process was started in 2003 and led to the R6RS Scheme standard in 2007. Academic use of Scheme for teaching computer science seems to have declined somewhat. Some universities are no longer using Scheme in their computer science introductory courses.[citation needed]
There are several new dialects of Lisp: Arc, Nu, and Clojure.
The two major dialects of Lisp used for general-purpose programming today are Common Lisp and Scheme. These languages represent significantly different design choices.
Common Lisp is a successor to MacLisp. The primary influences were Lisp Machine Lisp, MacLisp, NIL, S-1 Lisp, Spice Lisp, and Scheme.[26] It has many of the features of Lisp Machine Lisp (a large Lisp dialect used to program Lisp Machines), but was designed to be efficiently implementable on any personal computer or workstation. Common Lisp has a large language standard including many built-in data types, functions, macros and other language elements, as well as an object system (Common Lisp Object System or shorter CLOS). Common Lisp also borrowed certain features from Scheme such as lexical scoping and lexical closures.
Scheme (designed earlier) is a more minimalist design, with a much smaller set of standard features but with certain implementation features (such as tail-call optimization and full continuations) not necessarily found in Common Lisp.
Scheme is a statically scoped and properly tail-recursive dialect of the Lisp programming language invented by Guy Lewis Steele Jr. and Gerald Jay Sussman. It was designed to have exceptionally clear and simple semantics and few different ways to form expressions. A wide variety of programming paradigms, including imperative, functional, and message passing styles, find convenient expression in Scheme. Scheme continues to evolve with a series of standards (Revisedn Report on the Algorithmic Language Scheme) and a series of Scheme Requests for Implementation.
Clojure is a recent dialect of Lisp that principally targets the Java Virtual Machine, as well as the CLR, the Python VM, the Ruby VM YARV, and compiling to JavaScript. It is designed to be a pragmatic general-purpose language. Clojure draws considerable influences from Haskell and places a very strong emphasis on immutability.[27] Clojure is a compiled language, as it compiles directly to JVM bytecode, yet remains completely dynamic. Every feature supported by Clojure is supported at runtime. Clojure provides access to Java frameworks and libraries, with optional type hints and type inference, so that calls to Java can avoid reflection and enable fast primitive operations.
In addition, Lisp dialects are used as scripting languages in a number of applications, with the most well-known being Emacs Lisp in the Emacs editor, AutoLisp and later Visual Lisp in AutoCAD, Nyquist in Audacity. The small size of a minimal but useful Scheme interpreter makes it particularly popular for embedded scripting. Examples include SIOD and TinyScheme, both of which have been successfully embedded in the GIMP image processor under the generic name “Script-fu”.[28] LIBREP, a Lisp interpreter by John Harper originally based on the Emacs Lisp language, has been embedded in the Sawfishwindow manager.[29] The Guile interpreter is used in GnuCash. Within GCC, the MELT plugin provides a Lisp-y dialect, translated into C, to extend the compiler by coding additional passes (in MELT).
Lisp was the first homoiconic programming language: the primary representation of program code is the same type of list structure that is also used for the main data structures. As a result, Lisp functions can be manipulated, altered or even created within a Lisp program without extensive parsing or manipulation of binary machine code. This is generally considered one of the primary advantages of the language with regard to its expressive power, and makes the language amenable to metacircular evaluation.
The ubiquitous if-then-else structure, now taken for granted as an essential element of any programming language, was invented by McCarthy for use in Lisp, where it saw its first appearance in a more general form (the cond structure). It was inherited by ALGOL, which popularized it.
Lisp deeply influenced Alan Kay, the leader of the research on Smalltalk, and then in turn Lisp was influenced by Smalltalk, by adopting object-oriented programming features (classes, instances, etc.) in the late 1970s. The Flavours object system (later CLOS) introduced multiple inheritance.
Lisp introduced the concept of automatic garbage collection, in which the system walks the heap looking for unused memory. Most of the modern sophisticated garbage collection algorithms such as generational garbage collection were developed for Lisp.
Largely because of its resource requirements with respect to early computing hardware (including early microprocessors), Lisp did not become as popular outside of the AI community as Fortran and the ALGOL-descended C language. Because of its suitability to complex and dynamic applications, Lisp is currently enjoying some resurgence of popular interest.
Emacs (pron.: /ˈiːmæks/) and its derivatives are a family of text editors that are characterized by their extensibility. The manual for one variant describes it as “the extensible, customizable, self-documenting, real-time display editor.”[2] Development began in the mid-1970s and continues actively as of 2013. Emacs has over 2,000 built-in commands and allows the user to combine these commands into macros to automate work. The use of Emacs Lisp, a variant of the Lisp programming language, provides a deep extension capability.
The original EMACS was written in 1976 by Richard Stallman and Guy L. Steele, Jr. as a set of Editor MACroS for the TECO editor.[3][4][5][6] It was inspired by the ideas of the TECO-macro editors TECMAC and TMACS.[7]
Emacs became, along with vi, one of the two main contenders in the traditional editor wars of Unix culture. The word “emacs” is often pluralized as emacsen by analogy with boxen and VAXen.[8]
The most popular, and most ported, version of Emacs is GNU Emacs, which was created by Stallman for the GNU Project.[9]XEmacs is a common variant that branched from GNU Emacs in 1991. Both of the variants use Emacs Lisp and are for the most part compatible with each other.
SLIME, the Superior Lisp Interaction Mode for Emacs, is an Emacs mode for developing Common Lisp applications. SLIME originates in an Emacs mode called SLIM written by Eric Marsden and developed as an open-source project by Luke Gorrie and Helmut Eller. Over 100 Lisp developers have contributed code to SLIME since the project was started in 2003. SLIME uses a backend called SWANK that is loaded into Common Lisp.
SLIME works with the following Common Lisp implementations:
So, you’ve gone and downloaded some elisp file (foo.el, say). Now, what do you do with it? Well, the community convetion on the matter is to toss .el files in, say, ~/elisp/ (an elisp directory in your home directory). Once you have such a directory you need to ensure that it’s present in Emacs’ load-path variable. This is typically done by adding something like this to your ~/.emacs file:
(add-to-list 'load-path "~/elisp")
Next, you’ll need to configure Emacs to load the new file. Most of the time, you should be able to add (require 'foo) to ~/.emacs (where foo means foo.el).
Simplify! Use install.el
That’s often all you have to do, but there are lots of exceptions. Fortunately, Stefan Monnier’s install.el handles the vast majority of elisp files you’ll run into, and is very easy to use itself. Install it by following my directions above. Now, whenever you’d like to install an elisp file, simply invoke the install-file command (via M-x install-file RET). That’s it!
– emacs24 will be updated only when I change the build process or when new emacs24 versions are realeased
– emacs-snapshot are updated between once a week and once every two weeks on average. These versions are created from those of Julien Danjou for Debian unstable: http://emacs.naquadah.org/.
To add this PPA:
$ sudo add-apt-repository ppa:cassou/emacs
$ sudo apt-get update
Then, for emacs-snapshot:
$ sudo apt-get install emacs-snapshot-el emacs-snapshot-gtk emacs-snapshot
*Or*, for emacs24:
$ sudo apt-get install emacs24 emacs24-el emacs24-common-non-dfsg
Adding this PPA to your system
You can update your system with unsupported packages from this untrusted PPA by adding ppa:cassou/emacs to your system’s Software Sources. (Read about installing)
REMnux is a lightweight Linux distribution for assisting malware analysts with reverse-engineering malicious software. The distribution is based on Ubuntu and is maintained by Lenny Zeltser. John H. Sawyer March 22, 2012 In my last blog about Linux Live Environments, I mentioned REMnux, an environment specifically built for malware analysis. I’d spent a little time […]
REMnux is a lightweight Linux distribution for assisting malware analysts with reverse-engineering malicious software. The distribution is based on Ubuntu and is maintained by Lenny Zeltser.
Since I just received the new “Practical Malware Analysis” book from No Starch Press, the detailed lab exercises seemed like a perfect way to test out the tools included in REMnux. While most of the tools in the book are Windows-based, there are Linux-based equivalents found on REMnux.
The first task was downloading the lab files linked from http://practicalmalwareanalysis.com/labs and extracting them.
WARNING: The lab binaries contain malicious code and you should not install or run these programs without first setting up a safe environment.
Compatibility: The labs are targeted for the Microsoft Windows XP operating system. Many of the labs work on newer versions of Windows, but some of them will not. The labs are designed to mimic realistic malware. Some of them are well-written code that runs reliable and some of them (just like real malware) are poorly written code that may crash, contain memory leaks, or otherwise behave unexpectedly.
My plan to solely use REMnux was immediately thwarted by the self-extracting Windows executable that contained the lab files. There was a EULA (end user license agreement) wrapper as part of the executable that had to be accepted before the files could be extracted — a problem solved with a quick boot of a Windows XP virtual machine. Ideally, the authors will replace or supplement the self-extracting executable with a standard zip file.
After a quick and easy read through the first few chapters, I started to dig into the lab examples using REMnux’s tools. Chapter 1′s labs want you to upload the example binaries to VirusTotal to see whether any antivirus products detect them as possible malware. While I could have used Firefox to upload the files, I chose to use pyew’s “vt” plugin that searches VirusTotal using the MD5 hash of the file instead of uploading the actual file.
Searching just using the MD5 could have backfired if no one had uploaded the file to VirusTotal yet, but given the popularity of the book, the lab files had already been uploaded many times. It doesn’t appear that REMnux currently comes with a command-line tool to upload files to VirusTotal, so here are a couple of options (#1 and #2) that simply require that you get a free API key from VT first.
A few other tasks in the first few “Practical Malware Analysis” labs include looking at executables’ import/export functions, compile date, and packer identification. Pescanner works pretty well to figuring out those answers, but not all of them. For example, pescanner identifies suspicious import functions but does not list them all, and it incorrectly identified some of the executables as having been packed when they weren’t. Pyew faired better by being able to list all imports and exports and correctly identifying the packer, but it did not have an obvious way to show the compile date. But when used together, you can get the exact answers you need.
The last lab in Chapter 1 asks you to use Resource Hacker to look for resources that are stored in the file. To accomplish the same task on Linux, a command-line tool can be used called hachoir-subfile. Running hachoir-subfile against the Lab 1-4 executable will extract the embedded in PE file.
I’m looking forward to digging into the book more and using REMnux further to see just what I can do without having a Windows virtual machine. It’s not that I have anything against Windows — I just like to find alternative Linux-based tools that do the same thing as Windows-based tools. There’s definitely an advantage to having both platforms available for analysis with the plethora of tools to use.
I highly recommend taking a look at the “Practical Malware Analysis” if you’re interested in the topic, as it is one of the best books I’ve seen on subject and the labs are great. I suspect I’ll have more blogs in the future about the book and tools as I spend more time with it and find alternative tools to use for the analysis.
John Sawyer is a Senior Security Analyst with InGuardians. The views and opinions expressed in this blog are his own and do not represent the views and opinions of his employer. He can be reached at johnhsawyer@gmail.com and found on Twitter @johnhsawyer.
There are many ways to create a live USB drive carrying an operating system like Ubuntu, but the method I will describe further is mainly based on using SUN’s VirtualBox. While the method described on the Ubuntu documentations implies installing a Live CD image on a USB flash drive, which would then need to extract […]
There are many ways to create a live USB drive carrying an operating system like Ubuntu, but the method I will describe further is mainly based on using SUN’s VirtualBox. While the method described on the Ubuntu documentations implies installing a Live CD image on a USB flash drive, which would then need to extract and load the operating system in the RAM, the method that I will describe on this page implies installing a fresh operating system on a bootable flash drive that will work the same way as from a real HDD (except the speed, of course). Thus, you should have a good bootable USB 2.0, with decent I/O data processing speeds, with at least 4GB (considering that the operating system itself weighs ~2GB, Karmic Koala).
Divide your USB flash drive into two partitions
In order to separate the operating system from the documents you would like to save on the flash drive, it is advisable that you divide your USB flash drive into two partitions. Only do this if your USB flash drive has more than 2GB of space and you do not need to save changes you make inside the operating system. In order to achieve this, you need to have GParted installed (or at least this is what i prefer). If you are not following this tutorial on a Linux machine, then you’ll have to use whatever software you best know that works with your operating system (on Windows I recommend Acronis Disk Director and Partition Magic). To get GParted type the following command in a terminal:
sudo apt-get install gparted
Now backup all data you have on your USB flash drive, because we will need to format it and create two partitions. Haven’t backed up your data? You’re playing with fire!
UNetbootin (Universal Netboot Installer) is a cross-platform utility that can create live USB systems and can load a variety of system utilities or install various Linux distributions and other operating systems without a CD.
Can load a variety of system utilities, such as Ophcrack, BackTrack.
Other operating systems can be loaded via pre-downloaded ISO image or floppy/hard drive disk image files.
Automatically detects all removable devices.
Supports LiveUSB persistence (preserving files across reboots; this feature is for Ubuntu only)
Multiple installs on the same device are not supported.
It is worth noting that UNetbootin’s meta-data is very out of date. For example, the latest version of Linux Mint offered in the drop-down menu is version 10, whilst the latest official release is version 14 (at time of writing, February 2013). However, UNetbootin can still be used to write a bootable Mint 14 ISO file onto a USB device, if the user first downloads the ISO file manually.
These can contain just about any tool you want: anti-virus, OS boot cd’s, OS repair / recovery discs, programs, etc.) This is a slightly more difficult section depending on exactly what you want on your flash drive. This can also be time consuming.
Different programs and bootable Windows and Linux ISO’s require different boot parameters. Which is why some things work with one program and not another.
SARDU, XBOOT, and YUMI can create a multiboot utility flash drive but each officially support different programs / ISO’s. EasyBCD can create multiboot flash drives but requires you to PAY ATTENTION when configuring.
You’ll have to find which actually work best for you.
I haven’t found one that does everything I would like it to (do all the programs below and work) so I’ve got 2 utility / rescue flash drives.
Places to find help for the above programs.
1 – See the links on those programs home pages.
2 – Reboot.Pro
3 – 911CD
Additions Tested :
– Windows 7 Recovery Discs (32 & 64-bit)
– Windows Vista Repair Discs (32 & 64-bit)
– UBCD4Win (SP3 slipstreamed pre-build, nlited to add drivers and update packs)
– Hiren’s Boot CD 14
– openSUSE 11.4 LiveCD (KDE)
– Linux Mint LiveCD (Gnome & KDE) (if Linux Mint works then Ubuntu should too)
– AVG
– Avira
– Kaspersky
– Microsoft Standalone System Sweeper
– Acronis True Image Home 2011
– Acronis Disc Director 11
Below are some notes on each program as of this writing.
They are not intended to bash anyone, they are just the results I came up with.
SARDU ( 2.0.3 beta 6)
– Do not rename ISO’s.
– openSUSE does not work.
– Hiren’s Boot CD support removed AFAIK due to it’s questionable legality. (download v2.0.2c if you need this)
– UBCD4Win does not work in this version. (download v2.0.2c if you need this)
– Microsoft Standalone System Sweeper supported.
– To add Acronis to this see here.
Make sure all your ISO’s are in one folder.
Do not rename the ISO’s.
If you haven’t already downloaded them. Click the button next to the check box will take you to the download page.
Plug in your preformatted flash drive
Click the CD/ISO picture (upper left) to load the ISO folder.
ISO’s already in the folder will be preselected.
Click the Search USB button on the right to find your flash drive.
Click the picture of the flash drive below it to start the process of making your bootable flash drive.
SARDU creates a multiboot USB drive, a multiboot DVD or multiboot CD (all-in-one) for free (personal and non commercial use, read the license). Hard disks (internal and external), SSD, USB flash drive and all removable memory disk and media are supported.
The multi bootable device can include comprehensive collections of antivirus rescue CD, utilities and popular Linux live distributions. Windows PE can also be included, as well as recovery disks and install media for Windows XP (Professional, Home and 64 Bit), Windows Vista, Windows Seven and Windows Eight.
A search led to a recommendation that I try XBOOT. Another source suggested that SARDU and XBOOT both might be more robust than YUMI.
Were there other possibilities? An AlternativeTo webpage listed Universal USB Installer (of which UNetbootin was apparently a clone) and WinToFlash as much more popular than SARDU, XBOOT, or YUMI, but these did not appear to be multiboot solutions. That is, they would load only one program onto the USB drive. At this point, Wikipedia’s list of tools to create live USB systems did not distinguish multiboot from single-boot tools — but it did make clear that there were many single- or multiboot tools out there. One source offered a way to use UNetbootin to create a multiboot flash drive, but it, too, sounded complicated. A search suggested that EasyBCD was another possibility, but it appeared that it was a boot manager that would let you decide whether to boot from, say, a hard drive partition containing Windows 7 rather than another partition containing Linux.
So I took it as a choice among YUMI, SARDU, or XBOOT. A search led to a thread with several user reports that tended to favor YUMI. As I had also found, one comment recommended formatting within YUMI rather than formatting the USB drive via Windows Explorer. One blogpage, written in spring 2011, seemed to find little difference in capabilities, between SARDU and YUMI, except that SARDU had the advantage of allowing the user to burn a CD or DVD containing one (or possibly more) installer. Two other webpages praised SARDU, but without offering specific comparisons against alternatives like YUMI. The XBOOT webpage seemed to indicate, as others had done, that XBOOT was preprogrammed to accept far fewer programs and distributions than YUMI; the same had also seemed to be true of SARDU.
YUMI (Your Universal Multiboot Installer), is the successor to MultibootISOs. It can be used to create a Multiboot USB Flash Drive containing multiple operating systems, antivirus utilities, disc cloning, diagnostic tools, and more. Contrary to MultiBootISO’s which used grub to boot ISO files directly from USB, YUMI uses syslinux to boot extracted distributions stored on the USB device, and reverts to using grub to Boot Multiple ISO files from USB, if necessary.
Aside from a few distributions, all files are stored within the Multiboot folder, making for a nicely organized Multiboot Drive that can still be used for other storage purposes.
Creating a YUMI Multiboot MultiSystem Bootable USB Flash Drive
YUMI works much like Universal USB Installer, except it can be used to install more than one distribution to run from your USB. Distributions can also be uninstalled using the same tool!
XBOOT is yet another neat little Multiboot ISO USB Creator. It is a Windows based application that can be used to create a Live Multiboot USB or even a Multiboot ISO file that can then be burnt to a CD/DVD. XBOOT supports many Linux Distributions and Utilities, and allows you to use your choice of a Grub or Syslinux bootloader. Also included is a built in QEMU emulator (enabling you to boot an ISO from within Windows).
This software boots your PC and analyse your filesystems. It displays a graphical menu for you to select which system to boot. Intended to replace LILO and Loadlin, written in C with GCC, fully real mode.
It can read FAT12, FAT16, FAT32, ext2, ext3, ext4 (with constant inode size) and ISO 9660 filesystems.
It has a graphical user interface with mouse support, and can be installed on any media: floppy, hard/USB disk partitions, hard/USB disk MBR, CD/DVDROM, DVD-ram (i.e. FAT with 2048 bytes/sectors). It can also use a serial port as input/ouput instead of the screen and keyboard.
Gujin can chain-load other bootloader, load Linux kernel, has an unfinished loader of multiboot specification, but more importantly for our current interest it can load standard ELF files (more exactly GZIP compressed ELF files).
There is two major ELF variant on the PC: ELF32 (with 32 bits load address, sizes and entry point) and ELF64 (with 64 bits fields), gujin loads any of them and switch the processor in protected mode to jump to the ELF entry point.
Gujin will not try to set-up memory paging at all, that is the job of the kernel to select which kind of paging it wants – so even the 64 bits ELF files will have to handle the transition from 32 bits to 64 bits themselves (because you need paging to go to 64 bits mode).
Same for interrupts, Gujin switches to protected mode but does not re-enable interrupts, that is the job of the kernel being booted to set-up the Interrupt Decriptor Table and handle each interrupts, because BIOS will not help the kernel any more.
Gujin can also relocate the ELF file if it contains relocation information, see option –emit-relocs of the “ld” linker of the “binutils” toolchain.
Because most applications will want to collect BIOS informations before the switch to protected mode, Gujin can call in real-mode a function of the ELF file, and if this function returns zero – continue the loading process – else display an error message (for instance: “trying to execute a 64 bits application on a processor without this feature!”).
Moreover, in most cases the kernel can decide to return to the Gujin bootloader (if it did not erased it from memory), without forcing a reboot.
The Gujin bootloader is built using standard Linux tools, it does not need Linux to run (only a not-too-buggy BIOS) – but we have to assume you are running Linux to use the GNU toolchain: GCC, binutils, GZIP… to produce the ELF file for the kernel. Also, Gujin installer needs either Linux 32 bits or Linux 64 bits to run and install the Gujin bootloader on a device.
Because Windows uses another executable format, you cannot install cygwin/MinGW on windows and use the compilation toolchain directly, in this case you would have to generate a cross compiler toolchain to produce ELF files, and that is out of scope for this description (but not that difficult).
So enough text description, let’s try it!
The floppies being out-dated, let’s say we want to use a USB stick as our test media. In some cases, we may want to use a SD card, basically the process is the same.
We first need to check that the target PC will be able to boot that USB stick or SD card, when Gujin is installed on it.
To have increased chances of success, we will ask the Gujin installer to reformat completely this USB disk or SD card, so first backup any interresting file you have in some other place.
If you do not trust anybody, download the source file gujin-*.tar.gz, extract it in a directory and type “make” – that will produce an executable named “gujin” (even on a 64 bits Linux).
Remember to visit http://gujin.org to check if there is a newer version of Gujin, and to increase Gujin author counters and keep him happy.
Then, we reformat that dedicated USB stick as a bootable FAT filesystem, erasing all its content: first go in “root” by typing “su” or “sudo” (distribution dependant), then get the device name of you USB stick (let’s say it is /dev/sdg) (sometimes /dev/mmcblk0 for SD cards), and type:
./gujin /dev/sdg --disk=BIOS:0x00,auto
Depending on the size of the USB stick, that will have created either a FAT16 or a FAT32 (or even a FAT12) filesystem, but that point is not really important.
You then unplug this device, and replug it: most distribution will automatically mount the filesystem and display a window of its content: only a single file which is the bootloader itself.
To check that this filesystem is correctly created, you can type:
/sbin/fsck.vfat /dev/sdg
With the Gujin installer parameters we used, that would have created a “superfloppy” format on our USB stick, that is currently the format most PC will be able to understand and boot from.
That does not mean your own PC will 100% boot it, due to BIOS bugs – so you need to test now that this USB stick is bootable by your PC or not: umount the USB stick, plug it in the test PC and power it on, see if Gujin is started (you will notice easily).
If it is not started try to check:
- that the boot order in the BIOS is set to boot USB devices first
- try the different USB devices if your BIOS has switchable items.
- try to tell the Gujin installer to use the Extended BIOS instead by typing (--disk=EBIOS:0x00,auto is the default):
./gujin /dev/sdg
- try to tell the Gujin installer to generate a real disk and not a superfloppy by:
./gujin --mbr /dev/sdg --disk=BIOS:0x00,auto
- try the two previous options together:
./gujin --mbr /dev/sdg --disk=EBIOS:0x00,auto
- try to use another (smaller) USB stick, some BIOS will only accept to boot from a FAT16 superfloppy
By now you should know a lot more about your BIOS, and have a bootable USB stick.
Then, we want to generate this ELF kernel – let’s try to generate a “hello world”: Create a file with that content:
const char msg1[] = "Hello protected-mode text world! please reboot ...";
#define STACKSIZE 64 * 1024
static unsigned stack[STACKSIZE / 4] __attribute__ ((aligned(32)));
void _start (void)
{
/* We are flat non-paged memory and interrupt disabled */
asm (" mov %0,%%esp " : : "i" (&stack[STACKSIZE / 4]));
volatile unsigned short *video_array = (volatile unsigned short *)0xB8000;
unsigned cpt1;
video_array += 10 * 80; /* few empty lines */
/* We want blue background color and lightgray foreground, so 0x1700: */
for (cpt1 = 0; cpt1 < sizeof(msg1) - 1; cpt1++)
video_array[cpt1] = 0x1700 + msg1[cpt1];
while (1)
continue;
}
Then compile it like (you may need to add “-fno-stack-protector” too, distribution dependant):
You just need to copy that hello.kgz file into the USB stick, and reboot with this USB stick, you will get a menu with “hello.kgz” displayed.
If you click on this filename, you will have “Hello protected-mode text world! please reboot …” displayed (Because this hello-world do not manage graphic modes, you have to “force start kernel in text mode” in Gujin configuration).
If you want a bit more complex “hello world” applications, you should download Gujin install*.tar.gz pack .
you will find there few KGZ files, like previous example but with some addresses displayed to show the exact position of the application in memory.
you can copy this hello_bios.kgz to the USB stick and run it, I hope the different functions of the source file are obvious.
The Gujin bootloader is willing to let the real mode and protected mode kernel to access the bootloader internal data (like what is the current video mode, how to display strings…) as long as the kernel is licensed under the GPL license – i.e. when the GZIP kernel contains a GZIP comment describing its license. That is illustrated by cleandisk.kgz compiled form this cleandisk.c source code and linked with this linker file.
The main point about the GPL license is that it is not possible to draw a line in between Gujin possible bug and a closed source application: it is no allowed to modify Gujin data while in real mode – but there isn’t any enforcement by hardware.
Obviously, Gujin will enable you to run an ELF file with a real mode part AND a protected mode part, just have a look at the example hello_gpl.kgz and its source code hello_gpl.c.
Ahora, como antes, más que antes, como siempre, la reutilización de código se presenta como un valor fundamental en el desarrollo de sistemas. Uno de sus aspectos es la interoperabilidad de los códigos. Por decirlo de alguna manera, la compatibilidad de una aplicación con diferentes versiones de un sistema operativo y con diferentes sistemas operativos. […]
Ahora, como antes, más que antes, como siempre, la reutilización de código se presenta como un valor fundamental en el desarrollo de sistemas. Uno de sus aspectos es la interoperabilidad de los códigos. Por decirlo de alguna manera, la compatibilidad de una aplicación con diferentes versiones de un sistema operativo y con diferentes sistemas operativos.
Por un lado Microsoft, por otro los demás. El imperio contra los rebeldes republicanos y los feudos vecinos. Pero dentro del mismo imperio se hablan distintas lenguas y los rebeldes tienen diferentes agendas.
Una aplicación que trabaja en Windows 95 no necesariamente funciona en Windows XP, Visual Basic 6 y Visual Basic .Net son animales distintos. Una aplicación Linux que funciona en la distribución Red Hat no necesariamente funciona en la distribución SuSe. La frase platform independent source en la practica marca una prueba de iniciación para hechiceros.
En el caso de Microsoft, algunas de estas incompatibilidades son de origen mercadológico. ¿Cuál es la diferencia entre Windows XP Home Edition y Windows XP Pro? Limitaciones artificiales en la versión casera con respecto a la versión profesional. Desde el punto de vista de Microsoft este modelo funciona, Vista no tiene 2 versiones distintas sino n, cada una definida por un segmento de mercado. Las utilidades de MS aumentaron 65% con respecto al año pasado y podemos esperar más de lo mismo por lo menos en el corto plazo.
En el caso del movimiento Open Source las incompatibilidades son de origen sociocultural. Distintos grupos trabajan con combinaciones distintas de herramientas y enfoques metodológicos. Estos herramentales se yuxtaponen unos con otros y las combinaciones son infinitas. La versión de gcc pude ser la diferencia clave para que un paquete se construya correctamente.
Una iniciativa que no termino de entender es Mono. El concepto es bueno, pero ya va un par de veces que trato de construir una aplicación .Net para fallar miserablemente. Al revisar la letra chiquita del readme aparece que la aplicación es Mono ¿Cuál es el caso de incluir archivos de solución y proyecto de Visual Studio si VS no puede construir la aplicación? ¿Si se requiere reproducir el ambiente de trabajo del desarrollador con librerías y variables de entorno porque no documentar esas dependencias? Entiendo que son pecadillos del bien intencionado pero se me escapa la motivación fundamental del chango.
Un aspecto problemático del desarrollo ínter plataforma son las interfaces graficas de usuario (GUI). Cada sistema operativo tiene su look-and-feel característico y el manejo eficiente de ventanas requiere el uso del API nativo correspondiente.
Un enfoque que se puede tomar es agregar una capa intermedia entre la aplicación y el sistema operativo que abstraiga la interacción entre la capa lógica y la interfase grafica a cambio de una penalización en el rendimiento. Algunos problemas que se pueden presentar con librerías de este tipo:
El uso de una capa intermedia adicional disminuye el rendimiento de la aplicación.
La librería necesaria para soportar la funcionalidad adicional de múltiples sistemas operativos aumenta le tamaño de las aplicaciones más alla de lo que se justifica con la funcionalidad de la aplicación misma. Por lo mismo el soporte para plataforma móvil no es adecuado
La apariencia de la aplicación no corresponde a la de una aplicación nativa y los diálogos son distintos a los que los usuarios usan normalmente.
La necesidad de definir un mínimo común denominador hace que se pierda la oportunidad de usar las características más avanzadas de un sistema operativo en particular.
El uso de librerías fuera de la esfera de influencia del sistema operativo anfitrión saca a la aplicación del ciclo de vida del mismo y dificulta el proceso de mantener alineadas las actualizaciones de la aplicación con cambios en el sistema operativo.
La tabla siguiente muestra un comparativo de librerías para desarrollo ínter plataforma.
Liberaría
Tamaño (MB)
Tamaño comprimido (MB)
Java
30+
15
GTK+
9+
4
QT
4+
2
wxWidgets
<1
<.5
Java es una norma abierta que funciona bien como propuesta ínter plataforma. La maquina virtual de java (JVM) aísla la aplicación del sistema operativo anfitrión y esta disponible normalmente en todas partes. Sin embargo las aplicaciones de java tienden a ser chupa recursos. Si revisas los procesos en una estación XP con Firefox instalado, Firefox es normalmente el campeón en memoria utilizada.
GTK+ es un grupo importante de bibliotecas o rutinas para desarrollar interfaces gráficas de usuario (GUI) para principalmente los entornos gráficos GNOME, XFCE y ROX de sistemas Linux. GTK+ es la abreviatura de GIMP toolkit (conjunto de rutinas para GIMP). Es software libre (bajo la licencia LGPL), multiplataforma y parte importante del proyecto GNU. Inicialmente fue creado para desarrollar el programa de manejo de imágenes GIMP, sin embargo actualmente es muy usada por muchos otros programas en los sistemas GNU/Linux. Cabe mencionar que Qt es una alternativa a GTK que también es muy utilizada (en el entorno KDE, por ejemplo).
GTK+ se ha diseñado para permitir programar con lenguajes como C, C++, Java (Sun), Perl o Python.
GTK ha sido portada a Windows pero el look-and-feel no es nativo.
Qt es una biblioteca multiplataforma para desarrollar interfaces gráficas de usuario. Fue creada por la compañía noruega Trolltech. Qt es utilizada en KDE, un entorno de escritorio para sistemas como GNU/Linux o FreeBSD, entre otros. Utiliza el lenguaje de programación C++ de forma nativa y además existen bindings para C, Python (PyQt), Java (Qt Jambi), Perl (PerlQt) y Ruby (QtRuby) entre otros. El API de la biblioteca cuenta con métodos para acceder a bases de datos mediante SQL, así como uso de XML y una multitud de otros para el manejo de ficheros, además de estructuras de datos tradicionales. Inicialmente Qt apareció como biblioteca desarrollada por Trolltech (en aquel momento “Quasar Technologies”) en 1992 siguiendo un desarrollo basado en el código abierto, pero no libre. Se usó activamente en el desarrollo del escritorio KDE (entre 1996 y 1998), con un notable éxito y rápida expansión.
Qt cuenta actualmente con un sistema de doble licencia: una GPL para el desarrollo de software de código abierto (open source) y software libre, y otra de pago para el desarrollo de aplicaciones comerciales. Las librerías Qt son también liberadas bajo licencia GPL para Windows y Mac.
wxWidgets son unas bibliotecas multiplataforma, freeware/Open Source para el desarrollo de interfaces gráficas programadas en lenguaje C++. Es una librería pequeña que encapsula en una interfase común llamadas al API nativo de cada sistema operativo.
wxWidgets usan una licencia GPL, concretamente la licencia L-GPL, similar a la GPL con la excepción de que el código binario producido por el usuario a partir de ellas, puede ser propietario, permitiendo desarrollar aplicaciones empresariales sin coste.
Las WxWidgets proporcionan una interfaz gráfica basada en las bibliotecas ya existentes en el sistema (nativas), con lo que se integran de forma óptima y resultan muy portables entre distintos sistemas operativos. Están disponibles para Windows, MacOS, UNIX/Linux, OpenVMS y OS/2. También pueden ser utilizadas desde otros lenguajes de programación, aparte del C++: Java, Javascript, Perl, Python, Smalltalk, Ruby
In order to add your launcher to the Unity Launcher on the left, you have to place your .desktop file at /usr/share/applications/ or at ~/.local/share/applications/. After moving your file there, search for it in the Dash (Windows key -> type the name of the application) and drag and drop it to the Unity Launcher. Now […]
In order to add your launcher to the Unity Launcher on the left, you have to place your .desktop file at /usr/share/applications/ or at ~/.local/share/applications/. After moving your file there, search for it in the Dash (Windows key -> type the name of the application) and drag and drop it to the Unity Launcher. Now your launcher (.desktop file) is locked on the Unity Launcher! If your desktop file cannot be found by doing a search from the Dash, you may need to read on…
To be more certain that your .desktop file will work properly, use the desktop file validator, which will notify you of any errors or omissions. If there are no errors, desktop-file-validator will exit silently.
Once the file validates correctly, install it to the default location (probably /usr/share/applications) using the desktop-file-install program. This step may require superuser privileges. The desktop-file-install program may add some lines of its own to your .desktop file. There is no need to have the .desktop file be executable by anyone.
Please note that desktop-file-validate tends to be oversensitive at times, which means that it can output error messages on perfectly working .desktop files. Those error messages should be better seen as warnings rather than anything else. For more information on desktop entry specification please refer to http://standards.freedesktop.org/desktop-entry-spec/latest/
[Desktop Entry]
Name=the name you want shown
Comment=
Exec=command to run
Icon=icon name
Terminal=false
Type=Application
StartupNotify=true
For extra options for your .desktop file you can visit this site. All the options available are very well described there.
You can also copy a existing application’s .desktop file from /usr/share/applications/to your ~/.local/share/applications/ and edit it to fit your needs.
ie: this will copy gedit .desktop file to the folder where the .desktop files should be saved for a user
cd ~/.local/share/applications
sudo cp /usr/share/applications/gedit.desktop .
After that open that location using nautilus ~/.local/share/applications/ and drag n drop the file you have just created to the Unity launcher.
Has an option instead of drag n dropping the file you can open dconf-editor (install it with sudo apt-get install dconf-tools or look for it in the USC) and navigate to desktop.unity.launcher and edit the key favorites by double clicking on the entries to the right of the key.
To add your custom launcher add it at the position you want with this format ‘/home//.local/share/applications/.desktop’. Don’t forget to respect the , and the spaces in that line and make sure that the line starts and ends with [ and ]respectively.
With this method you will need to log off and back in for the change in favorites to take effect. This will make it appear in the dash
Bash is a Unix shell written by Brian Fox for the GNU Project as a free software replacement for the Bourne shell (sh).[3][4] Released in 1989,[5] it has been distributed widely as the shell for the GNU operating system and as the default shell on Linux and Mac OS X. It has been ported to […]
The name itself is an acronym, a pun, and a description. As an acronym, it stands for Bourne-again shell, referring to its objective as a free replacement for the Bourne shell.[7] As a pun, it expressed that objective in a phrase that sounds similar to born again, a term for spiritual rebirth.[8][9] The name is also descriptive of what it did, bashing together the features of sh, csh and ksh.[10]
On systems like Ubuntu, most software is packaged in nice .deb (or .rpm, like in Red Hat) files which contain the programs and libraries you need. These files can be downloaded or come in CDs (Ubuntu’s CD is full of them). Repositories are servers which contain sets of packages. You generally access them with tools […]
On systems like Ubuntu, most software is packaged in nice .deb (or .rpm, like in Red Hat) files which contain the programs and libraries you need. These files can be downloaded or come in CDs (Ubuntu’s CD is full of them). Repositories are servers which contain sets of packages. You generally access them with tools like Synaptic.
These tools can list all the packages you have installed (from your kernel to your favorite application with all the libraries in between) and the packages that are available in the repositories that you have configured the tool to have access to. They also let you search for simple things like “image editor”.
These tools provide a simple, centralized method of software installation and give the distributors (who set up the repositories) a centralized way to send you updates(1) to your software.
In Ubuntu you generally want to have at least Ubuntu’s repositories (which may include the install CD) but it is not uncommon to have other repositories (from other packagers) set up.
It’s important to know that most of the tools you’ll want to use in Ubuntu are already in Ubuntu’s repositories. You can go search the internet for packages, or even source code, for others, but these will be more difficult to install and won’t, most of the time, integrate as well with your system.
So now you know: no more endless searching looking for spyware-infested shareware and freeware. The vast majority of useful software available for Linux is pre-packaged for you.
Components
Software in Ubuntu’s repository is divided into four categories or components – main, restricted, universe and multiverse.
Most people will use the Ubuntu Software Centre to install the software they want. But if you’re interested in learning more about the different categories of software we include, read on! Software is grouped according to our ability to maintain it and by how well it meets the goals of our free software philosophy. The standard Ubuntu installation is a collection of software from the main and restricted components. You can install additional software from the Ubuntu Software Centre.
Main
The main component contains applications that are free software, can be freely redistributed and are fully supported by the Ubuntu team. This includes the most popular and most reliable open-source applications available, many of which are included by default when you install Ubuntu. Software in main includes a hand-selected list of applications that the Ubuntu developers, community and users feel are most important, and that the Ubuntu security and distribution team are willing to support. When you install software from the main component, you are assured that the software will come with security updates and that commercial technical support is available from Canonical.
Restricted
Our commitment is to only promote free software – or software available under a free licence. However, we make exceptions for a small set of tools and drivers that make it possible to install Ubuntu and its free applications on everyday hardware. These proprietary drivers are kept in the restricted component. Please note that it may not be possible to provide complete support for this software because we are unable to fix the software ourselves – we can only forward problem reports to the actual authors. Some software from restricted will be installed on Ubuntu CDs but is clearly separated to ensure that it is easy to remove. We will only use non-open-source software when there is no other way to install Ubuntu. The Ubuntu team works with vendors to accelerate the open-sourcing of their software to ensure that as much software as possible is available under a free licence.
Universe
The universe component is a snapshot of the free, open-source, and Linux world. It houses almost every piece of open-source software, all built from a range of public sources. Canonical does not provide a guarantee of regular security updates for software in the universe component, but will provide these where they are made available by the community. Users should understand the risk inherent in using these packages. Popular or well supported pieces of software will move from universe into main if they are backed by maintainers willing to meet the standards set by the Ubuntu team.
Multiverse
The multiverse component contains software that is not free, which means the licensing requirements of this software do not meet the Ubuntu main component licence policy. The onus is on you to verify your rights to use this software and comply with the licensing terms of the copyright holder. This software is not supported and usually cannot be fixed or updated. Use it at your own risk.
A Quick, Tongue-in-cheek Description of the Ubuntu Repositories
$release: Don’t touch it, I like consistency, even with my bugs.
$release-security: I’ll accept patches to existing versions (and very rare version upgrades if absolutely necessary) in the process of keeping my system secure.
$release-updates: Okay, some bugs are worth fixing, and I trust you this much (holds up two fingers like Maxwell Smart).
$release-backports: I have something akin to technology ADHD, needing the latest of everything I can possibly get, but I can’t handle running the development branch.
$devel: I can take it. Seriously. If you break my X, I shall become more powerful than you could possibly imagine. I’ll file and maybe even fix the bugs and I’ll do it even if power management is not so much ‘managed’ as vomited all over the wall. Come get some.
Managing Personal or Local Repositories
If there are packages you want to load outside of the supported repositories, this page explains a way to ease package dependency issues.
Lubuntu is a fast and lightweight operating system developed by a community of Free and Open Source enthusiasts. The core of the system is based on Linux and Ubuntu . Lubuntu uses the minimal desktop LXDE, and a selection of light applications. We focus on speed and energy-efficiency. Because of this, Lubuntu has very low hardware requirements. Please join us and contribute to an exciting International Free and Open Source Software project. Install Lubuntu on your computer and start getting involved. Quick links for direct Downloads of the latest version:
PCs with the Windows 8 logo or UEFI firmware, choose the 64-bit download. Visit the help pages for more info about which download is best for you. The section discusses both the standard installs and those required for computers with low memory (RAM), old chipsets (i586) and low disk-space (netbooks).
SciTE is a SCIntilla based Text Editor. Originally built to demonstrate Scintilla, it has grown to be a generally useful editor with facilities for building and running programs. It is best used for jobs with simple configurations. SciTE is currently available for Intel Windows (XP or later) and Linux compatible operating systems with GTK+. It […]
SciTE is a SCIntilla based Text Editor. Originally built to demonstrate Scintilla, it has grown to be a generally useful editor with facilities for building and running programs. It is best used for jobs with simple configurations.
SciTE is currently available for Intel Windows (XP or later) and Linux compatible operating systems with GTK+. It has been run on Windows 7 and on Fedora 12 and Ubuntu 10.10 with GTK+ 2.20. Here is a screenshot of SciTE.
Questions and comments about SciTE should be directed to the scite-interest mailing list, which is for discussion of SciTE and related projects, their bugs and future features. This is a low traffic list, averaging less than 50 messages per week. To avoid spam, only list members can write to the list. New versions of SciTE are announced on scite-interest and may also be received by SourceForge members by clicking on the Monitor column icon for “scite” on the downloads page.
Lua’s name is not an acronym. It is properly spelled as “Lua” or occasionally “lua”, but never “LUA”. See lua.org/about.html for the whole story.
First of all work your way through the Programming in Lua, it should take you a day or two to get the gist of Lua. The book is free online. Besides it is the best tutorial out there on Lua,
Also: If you’re purpose is Lua for World of Warcraft (probably not but just in case) you can check out this tutorial
And: Here is a tips and tricks thread on StackOverflow, might help give you some ideas of what to expect from Lua
Suggested Programs/Exercises:
Since you’re initially looking at Lua for web development try to understand and improve the Data Description example in PIL. It’ll give you a few good ideas and a nice feel for the power or Lua.
Then you might want to try out playing with the Data Structures chapter, although Lua has a single complex data-type, the Table, that chapter will show you Lua-like ways to make a table do anything you need.
Finally once you begin to grok metatables you should design a class system (yes with Lua you decide how your class system works). I’m sure everyone that knows Lua has made a dozen class systems, a good chapter to get you started on a class system is Object-Oriented Programming
And if you got time and know C or something like that (C# and Java included) try extending an application with Lua, but that’ll take a week or two to do
To say it straight in only one sentence: gpg4usb is a very easy to use portable-application, which combines a simple text-editor with a GnuPG-frontend to write, encrypt and decrypt your text-messages and files. gpg4usb should work on almost any computer you’re working on, should it be a Linux-machine or even one with a Microsoft-OS running. Almost […]
To say it straight in only one sentence: gpg4usb is a very easy to use portable-application, which combines a simple text-editor with a GnuPG-frontend to write, encrypt and decrypt your text-messages and files. gpg4usb should work on almost any computer you’re working on, should it be a Linux-machine or even one with a Microsoft-OS running.
Almost the only thing required is an available usb-port you are allowed to access. With this application you can write safe and encrypted messages anywhere you are: should it be an internet-cafe, at work or somewhere else on holiday… and you always have the encryption-keys available for usage!
The usage of gpg4usb should be highly self-describing, since the user-interface and all the options it offers are clear cut: Simply execute the binary on your usb-pendrive and start typing e.g. the Mailtext you want to be encrypted. If you’re done, choose the right gpg/pgp-key for the person you are writing to and hit the encrypt-icon at the top of the application-window. The resulting encrypted text you can save as a text-file to send it as mail-attachment, or copy it directly into your mail-user-agent or webmail-website. To make sure, you can read this message by yourself afterwards, encrypt it for the recipient and to yourself at the same time – if you want, you can mark as much keys as you want to encrypt for.
You want to add a gpg/pgp-key to your mobile keyring? Nothing’s easier than that: just hit the crypto-menue-entry and choose Import Key from File or Import Key from Editor. This means that it’s possible to import an ascii-armored pubkey via file-dialog, or via copy&paste into your editor-window. If you find a key e.g. on a website, just copy it, paste it into the gpg4usb-editor and hit Import Key from Editor – that’s it, and the key shows up on your keyring!
Just download the zip-File and unzip it onto your usb-pendrive. Then simply change into the folder gpg4usb at your usb-drive, and execute the binary in there:
start_linux or start_windows.exe – should be easy to determine, which one’s yours
Since gpg4usb is free software, licensed under the GNU General Public License (GPL), you can use it on as many machines as you want. Copy it, modify and redistribute it, give gpg4usb to as many people as possible!
