Strings are commonly encoded as hexadecimal (hex) strings for various purposes. Hence, it is also common to convert hex strings to its original strings such as an ASCII string. Hex to ASCII string conversion can be done programmatically in many languages. In command line, we can use xxd to convert hex to ASCII string. This
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Tag: PS
Release Notes For Linux v2.0
Posted onThis is the release notes for linux release v2.0 (source code: linux-2.0.tar.gz) with format adjusted by removing/replacing tabs/spaces/new lines/formatting marks. This notes document can give us an understanding of the early development of the Linux kernel. The original ASCII formatted version is at the end of this post. Intro This document contains a list of
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Release Notes For Linux v1.0
Posted onThis is the release notes for linux release v1.0 (source code: linux-1.0.tar.gz) with format adjusted by removing/replacing tabs/spaces/new lines. This notes document can give us an understanding of the early development of the Linux kernel. The original ASCII formatted version is at the end of this post. CHANGES since 0.99 patchlevel 15: removed all the
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Release Notes For Linux v0.97
Posted onThis is the release notes for linux release v0.97 with format adjusted by removing/replacing tabs/spaces/new lines. This notes document can give us an understanding of the early development of the Linux kernel. The original ASCII formatted version is at the end of this post. Changes in 0.97: The VESA-support was removed. I’d be happy to
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Where is MySQL / MariaDB storage location by default on CentOS 7?
Posted onWhere is MySQL / MariaDB storage location by default on CentOS 7? No special configuration to the MariaDB from official repository of CentOS. On CentOS 7 Linux it is usually by default /var/lib/mysql But here I give you another “hacky” way to find it out. The method is to find out the mysql daemon mysqld’
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Killing Running Bash Script Process Itself and All Child Processes In Linux
Posted onIn Linux, how to kill a process and all its child processes? For example, a Bash script A starts B, B starts C and C calls rsync. I would like to kill A and all its child processes all together. How to do this? There are possibly many answers to this question. One of the
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Where is the source code for the free command on Linux?
Posted onWhere can I find the source code for the free command on Linux? The source code for the free commands (and many more, like kill, ps, top, sysctl) can be found in procps-ng: https://gitlab.com/procps-ng/procps procps is a set of command line and full-screen utilities that provide information out of the pseudo-filesystem most commonly located at
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How to get a free Web server SSL/TLS certificates for my websites?
Posted onCan I get a non-self-assigned and free Web server SSL/TLS certificates for my https websites? Asking the users to accept the self-assigned SSL certificates for my websites is not very convenient. Please check https://letsencrypt.org/ . PS: StartSSL used to provide 1 year free SSL. But StartCom CA is closed since Jan. 1st, 2018.
Making Hadoop Java process heap larger?
Posted onIn Hadoop 2.5.0, I use ‘ps -aux’ and find the Java process has options: -Xmx1000m However, my nodes have 32GB memory. How to make Hadoop Java process heap larger? In yarn-env.sh, you can find: # For setting YARN specific HEAP sizes please use this # Parameter and set appropriately # YARN_HEAPSIZE=1000 In hadoop-env.sh, you can
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Ghostscript reports “Unrecoverable error: stackunderflow in .setdistillerparams”
Posted onWith the command -dPDFSETTINGS=/print for ps2pdf, I got: GPL Ghostscript 9.10: Set UseCIEColor for UseDeviceIndependentColor to work properly. Unrecoverable error: stackunderflow in .setdistillerparams make: *** [pdf-print] Error 255 How to fix it? I use this workaround: ps2pdf -dColorConversionStrategy=/LeaveColorUnchanged -dPDFSETTINGS=/printer psfile.ps from this. An alternative is to use -dPDFSETTINGS=/prepress.
How to make eps files using gnuplot
Posted onHow to make gnuplot generate eps files instead of plot the figures on screen? First, save a Gnuplot plot as a PostScript file by this commands: # gnuplot> load ‘saveplot’ # gnuplot> !mv my-plot.ps another-file.ps The saveplot file’s content: set size 1.0, 0.6 set terminal postscript portrait enhanced mono dashed lw 1 “Helvetica” 14 set
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How to compile Latex on Linux
Posted onHow to compile Latex on Linux, and what’s the needed packages? On Fedora, the packages needed can be simply installed via: # yum install texlive* dvipdfmx To compile a latex document (say doc.tex) with bibtex used: $ latex doc $ bibtex doc $ latex doc $ latex doc $ dvips doc.dvi $ ps2pdf doc.ps The
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How to convert a ps file to a pdf file
Posted onHow to convert a ps file to a pdf file that is available for publish (embedded fonts, etc)? Convert the file.ps ps file to file.pdf: $ ps2pdf -dPDFSETTINGS=/printer file.ps file.pdf</pre> Embedding Fonts in PDFs with pdflatex by Jeffrey P. Bigham: http://www.manticmoo.com/articles/jeff/programming/latex/embedding-fonts-with-pdflatex.php
How migration thread works inside of Linux Kernel
Posted onAbstract In computer systems, resources have to be balanced so that the performance will be better based on the same hardware. In Linux Kernel system, we will see some migration kernel threads running as daemons to do this kind of jobs as follows. In this article, we will discuss how Linux Kernel balances its hardware/software
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pkill and pgrep: Process Management Commands
Posted onThis is a introduction to *nix’s process management tools: pkill and pgrep. As this site’s domain name was pkill.info, a introduction to pkill should exist here. NAME pgrep, pkill – look up or signal processes based on name and other attributes SYNOPSIS pgrep [-flvx] [-d delimiter] [-n|-o] [-P ppid,…] [-g pgrp,…] [-s sid,…] [-u euid,…]
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A Simple Makefile for Latex
Posted onCompiling a latex documents may take several steps when bibtex is used with latex. However, this latex compilation process is the same for most documents. We can make it a template with Makefile so that simply running make will generate the dvi/ps/pdf files for us. A simple Makefile for using latex with bibtex enabled is
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How to Set Up Socks Proxy Using SSH Tunnel
Posted onWe can set up a socks proxy on top of a SSH tunnel. Besides the common proxy functions, such as web browsing, the proxy on top of SSH tunnel also ensures the security between the browser and the proxy server (the SSH server). In this post, we introduce and explain how to set up a
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