Commands using head (314)

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Backup with versioning
Apart from an exact copy of your recent contents, also keep all earlier versions of files and folders that were modified or deleted. Inspired by EVACopy http://evacopy.sourceforge.net

Recursively compare two directories and output their differences on a readable format

Runs previous command replacing foo by bar every time that foo appears
Very useful for rerunning a long command changing some arguments globally. As opposed to ^foo^bar, which only replaces the first occurrence of foo, this one changes every occurrence.

dd with progress bar and statistics to gzipped image
This is a useful command to backup an sd card with relative total size for piping to pv with a progressbar

Get current Xorg resolution via xrandr
Not sure if it works the same on any shell.

Print all environment variables, including hidden ones
This uses some tricks I found while reading the bash man page to enumerate and display all the current environment variables, including those not listed by the 'env' command which according to the bash docs are more for internal use by BASH. The main trick is the way bash will list all environment variable names when performing expansion on ${!A*}. Then the eval builtin makes it work in a loop. I created a function for this and use it instead of env. (by aliasing env). This is the function that given any parameters lists the variables that start with it. So 'aae B' would list all env variables starting wit B. And 'aae {A..Z} {a..z}' would list all variables starting with any letter of the alphabet. And 'aae TERM' would list all variables starting with TERM. $ aae(){ local __a __i __z;for __a in "$@";do __z=\${!${__a}*};for __i in `eval echo "${__z}"`;do echo -e "$__i: ${!__i}";done;done; } And my printenv replacement is: $ alias env='aae {A..Z} {a..z} "_"|sort|cat -v 2>&1 | sed "s/\\^\\[/\\\\033/g"' From: http://www.askapache.com/linux-unix/bash_profile-functions-advanced-shell.html

Route outbound SMTP connections through a addtional IP address rather than your primary

Create a bunch of dummy files for testing
Sometimes I need to create a directory of files to operate on to test out some commandlinefu I am cooking up. The main thing is the range ({1..N}) expansion.

Load all files (including in subdirs), whose name matches a substring, into Vim
This command searches the current directory, and all of its subdirs, for files that have the string "foo" in their filename (foo.c, two-foo.txt, index-FOO-bar.php, etc), and opens them in Vim. It ignores any hidden .svn directories. Change -iname to -name if you want to do case-sensitive matches. Files open in buffers by default, so to verify that the correct files were opened, type ":list". You can load all the files in tabs by doing ":tab ball" or use 'vim -p' on the command-line to load files straight to tabs. If you get permission denied errors, do: vim $(find . ! -path \*.svn\* -type -f iname \*foo\* 2>/dev/null) To narrow it down to a single file extension, such as .php files, use \*foo\*.php (or '*foo*.php'. Which ever you prefer)

Use top to monitor only all processes with the same name fragment 'foo'
top accecpts a comma separated list of PIDs.


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