Popular recipes tagged "unix" but not "python"

A utility like Unix seq (command-line), in Python (Python)

2017-01-08T17:48:57-08:00

Python recipe 580744 by Vasudev Ram (bash, command, commandline, linux, script, seq, sequence, shell, unix, utilities, utility).

This recipe shows how to create a utility like Unix seq (command-line), in Python. seq is described here:

https://en.wikipedia.org/wiki/Seq_(Unix)

but briefly, it is a command-line utility that takes 1 to 3 arguments (some being optional), the start, stop and step, and prints numbers from the start value to the stop value, on standard output. So seq has many uses in bigger commands or scripts; a common category of use is to quickly generate multiple filenames or other strings that contain numbers in them, for exhaustive testing, load testing or other purposes. A similar command called jot is found on some Unix systems.

This recipe does not try to be exactly the same in functionality as seq. It has some differences. However the core functionality of generating integer sequences is the same (but without steps other than 1 for the range).

More details and sample output are here:

https://jugad2.blogspot.in/2017/01/an-unix-seq-like-utility-in-python.html

The code is below.

A pseudo-echo, (or printf), function for any Python version. (Python)

2017-01-20T22:17:23-08:00

Python recipe 580750 by Barry Walker (amiga, apple, demo, echo, fs_uae, linux, printf, unix, windows, winuae).

A simple example of having a pseudo-echo using sys.stdout.write...

This gives exactly the same results from Python Versions, 1.4.0, 2.0.1, 2.5.6, 2.6.9, 3.4.3 and 3.5.2 on various platforms including the classic AMIGA A1200.

Enjoy finding simple solutions to often very difficult problems...

Bazza.

A simple raw hexdumper. (Python)

2016-09-19T13:24:37-07:00

Python recipe 580697 by Barry Walker (amiga, apple, fs_uae, hex, hexdump, linux, macbook_pro, raw_hexdump, unix, windows, winuae).

This is not a hexreader. This code creates a raw hexdump of a binary file that is whitespace, optional, delimited. The dump is saved into the current directory with a ".hex" extension.

It works on just about any current platform but is designed around a stock Amiga A1200(HD) with Python 1.4.0. It also works on the current stable version 3.5.2.

I needed a hexdump some years ago for banging the Amiga hardware, and decided to modify recently for another usage but it had to still work on version 1.4.0 for the classic A1200.

Enjoy...

data_dump.py, like the Unix od (octal dump) command (Python)

2015-11-01T12:43:38-08:00

Python recipe 579120 by Vasudev Ram (data, dump, hexadecimal, linux, octal, od, representation, unix, utility, windows).

This recipe implements a simple data dump tool, roughly like the od command of Unix, which stands for octal dump (though od can also dump data in hex and other formats). This tool dumps data in character and hex formats, in this version. This is data_dump.py version 1.

A UNIX-like "which" command for Python (Python)

2015-03-20T19:23:45-07:00

Python recipe 579035 by Vasudev Ram (bash, commandline, commands, linux, shell, unix, utilities, which).

UNIX users are familiar with the which command. Given an argument called name, it checks the system PATH environment variable, to see whether that name exists (as a file) in any of the directories specified in the PATH. (The directories in the PATH are colon-separated on UNIX and semicolon-separated on Windows.)

This recipe shows how to write a minimal which command in Python. It has been tested on Windows.

Send a message to remote syslog server (Perl)

2014-07-31T17:23:17-07:00

Perl recipe 578916 by Brett Carroll (perl, syslog, unix). Revision 2.

This script allows sending syslog messages to a remote syslog server (UNIX).

Create PDF at the end of a Unix pipeline with PDFWriter (Python)

2013-12-22T22:19:00-08:00

Python recipe 578794 by Vasudev Ram (commandline, linux, pdf, pipelining, reportlab, unix, xtopdf).

This recipe shows how to create PDF output at the end of a Unix or Linux pipeline, after all the text processing required, is done by previous components of the pipeline (which can use any of the standard tools of Unix such as sed, grep, awk, etc., as well as custom programs that act as filters).

Sleepsort with processes and pipes (Python)

2011-06-17T02:37:58-07:00

Python recipe 577758 by Benjamin Peterson (process, sorting, unix). Revision 2.

Sleepsort is a sorting algorithm that uses the system sleep syscall in a very creative fashion.

This is the same algorithm as recipe 577756 but using *nix processes instead of threads.

Get additional group IDs for Unix user (pwd/grp modules) (Python)

2011-06-03T02:14:18-07:00

Python recipe 577733 by realityexists (group, linux, passwd, security, unix).

The Python stdlib pwd module provides an easy way to get the primary group ID, but no way to get additional group IDs. This is a simple function that returns the additional group IDs for a given username.

Creating a tar archive (without using the tarfile module) (Python)

2010-10-11T06:18:42-07:00

Python recipe 577422 by Benjamin Sergeant (compression, tar, unix).

Creating a tar file is easy if you read the spec (you can look it up on wikipedia). Not every kind of files are supported (it support regular files, folders ans symlinks) and it's generating archives for the original tar file format (path length are limited to 100 chars, no extended attributes, ...). It wasn't tested very much but it was a fun hack :) ... I cheated just a little by looking at the python tarfile code from the stdlib for the checksum computation.

A tar file is very simple, it's a list of header/payload for each entry (file|folder|symlink) you want to archive. There's only a payload for file contents. The header is 512 bytes long and can be written in ascii. Numbers (attributes) needs to be written in octal. The files themselves needs to be written in chunks of 512 bytes, which mean you have to fill the last chunk with zeros when the file size is not a multiple of 512 bytes.

Use it like that:

python batar.py /tmp/foo.tar `find .` &&  tar tf /tmp/foo.tar # or xf if you want to extract it

Relative path from one directory to another without explicit string functions (unix only) (Python)

2011-04-11T13:02:32-07:00

Python recipe 577356 by Denis Barmenkov (path, relative, unix). Revision 4.

I saw a recipe 208993 messed up with os.sep and '../' and decide to write near-pure-Python version. os.sep used in string expressions only for testing for root directory.

Function deal with Unix paths (root: "/"), Windows systems are not supported (root: "C:\").

tgraph - Simple ASCII graphing utility (Python)

2011-07-28T21:13:23-07:00

Python recipe 577077 by Drew Gulino (ascii, graph, log, sysadmin, tail, unix).

Takes a stream of numbers and outputs simple ASCII graphs of those numbers

touch (Python)

2009-09-28T16:19:23-07:00

Python recipe 576915 by Trent Mick (file, shell, touch, unix).

Python function a la the Unix touch program (man touch).

Linux Terminal Color Setter (Python)

2008-09-11T17:08:30-07:00

Python recipe 576503 by Collin Stocks (just_for_fun, linux, terminal, unix).

This module can move the cursor around in the terminal, change the text color, highlighting color, et cetera, bold, underlined, flashing (if supported). It also has a word wrap function, and can center text.

unix subprocess wrapper (Python)

2008-07-29T07:11:17-07:00

Python recipe 576387 by Pádraig Brady (group, popen, subprocess, unix). Revision 2.

I have used this for ages to control child processes (and all their children). Some of the existing subprocess module was based on this, but I find this simpler for my uses at least.

Example:

import subProcess
process = subProcess.subProcess("your shell command")
process.read() #timeout is optional
handle(process.outdata, process.errdata)
del(process)

Listing the package/patches dependencies of a binary on Solaris (Python)

2008-07-30T04:30:44-07:00

Python recipe 576397 by Benjamin Sergeant (solaris, system, unix). Revision 2.

Print (1) packages used by a binary, and (2) the list of installed patches related to these packages. If you have a binary that works with Solaris 10 update N, but doesn't with Solaris 10 update N-2, run this script on both platform and it will help you to find the patches you're looking for.

(1) is retrieved:

By using pldd(pid) on the process you want to trace to get a list of loaded shared library
By retrieving in the main /var/sadm/install/contents database the list of package related to these shared libraries

(2) is retrieved by parsing the output of the showrev -p command, given as input of this script