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pattern match in awk - no grep
Rather than chain a string of greps together and pipe them to awk, use awk to do all the work. In the above example, a string would be output to stdout if it matched pattern1 AND pattern2, but NOT pattern3.

Create md5sum of a directory

Convert CSV to JSON
Replace 'csv_file.csv' with your filename.

SH
$ cat mod_log_config.c | shmore or $ shmore < mod_log_config.c Most pagers like less, more, most, and others require additional processes to be loaded, additional cpu time used, and if that wasn't bad enough, most of them modify the output in ways that can be undesirable. What I wanted was a "more" pager that was basically the same as running: $ cat file Without modifying the output and without additional processes being created, cpu used, etc. Normally if you want to scroll the output of cat file without modifying the output I would have to scroll back my terminal or screen buffer because less modifies the output. After looking over many examples ranging from builtin cat functions created for csh, zsh, ksh, sh, and bash from the 80's, 90s, and more recent examples shipped with bash 4, and after much trial and error, I finally came up with something that satisifed my objective. It automatically adjusts to the size of your terminal window by using the LINES variable (or 80 lines if that is empty) so This is a great function that will work as long as your shell works, so it will work just find if you are booted in single user mode and your /usr/bin directory is missing (where less and other pagers can be). Using builtins like this is fantastic and is comparable to how busybox works, as long as your shell works this will work. One caveat/note: I always have access to a color terminal, and I always setup both the termcap and the terminfo packages for color terminals (and/or ncurses and slang), so for that reason I stuck the $ tput setab 4; tput setaf 7 command at the beginning of the function, so it only runs 1 time, and that causes the -- SHMore -- prompt to have a blue background and bright white text. This is one of hundreds of functions I have in my .bash_profile at AskApache.com, but actually won't be included till the next update. If you can improve this in any way at all please let me know, I would be very grateful! ( Like one thing I want is to be able to continue to the next screen by pressing any key instead of now having to press enter to continue)

An easter egg built into python to give you the Zen of Python

Fixes Centos 6.2 yum's metalink certificate errors
Fix's centos 6.2 yum's error: could not get metalink https://mirrors.fedoraproject.org/metalink?repo=epel-6&arch=x86_64 error was 14: PYCURL ERROR 77 - "Problem with the SSL CA cert (path? access rights?)" Error: Cannot retrieve metalink for repository: epel-source. Please verify its path and try again

Find files changed between dates defined by ctime of two files specified by name
This command finds all the files whose status has changed between the ctime of the older and newer . Very useful if you can see from an ls listing a block of consecutive files you want to move or delete, but can't figure out exactly the time range by date.

check open ports without netstat or lsof

Start screen in detached mode
Start screen in detached mode, i.e., already running on background. The command is optional, but what is the purpose on start a blank screen process that way? It's useful when invoking from a script (I manage to run many wget downloads in parallel, for example).

Be notified about overheating of your CPU and/or motherboard
You'll be notified if your core 1 temperature exceeds 50 degrees, you can change the monitored device by editing the "Core 1" or change the critical temperature by editing the "-gt 50" part. Note: you must have lm-sensors installed and configured in order to get this command working.


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