Commands by xymor (2)

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Find out the starting directory of a script
Invoked from within a shell script, this will print the directory in which the script resides. Doesn't depend on external tools, /proc/self/*, etc.. (`echo` is a shell builtin.) To see the *current working* directory of a script, use `pwd`.

Summarise the size of all files matching a simple regex
Use the find command to match certain files and summarise their total size in KBytes.

shows the full path of shell commands

generate a telephone keypad
seems a useless command ...

Disable WoL on eth0

See system users

journalctl -f
a tail -f variant of systemd journal. Follow the most recent updates or if events are appended to the journal

Determine if a command is in your $PATH using POSIX
it is generally advised to avoid using which(1) whenever possible. which(1) is usually a csh(1) script, or sometimes a compiled binary. It's output is highly variable from operating system to operating system, so platform independent scripts could become quite complicated with the logic. On HP-UX 10.20, for example, it prints "no bash in /path /path /path ..."; on OpenBSD 4.1, it prints "bash: Command not found."; on Debian (3.1 through 5.0 at least) and SuSE, it prints nothing at all; on Red Hat 5.2, it prints "which: no bash in (/path:/path:...)"; on Red Hat 6.2, it writes the same message, but on standard error instead of standard output; and on Gentoo, it writes something on stderr. And given all these differences, it's still variable based on your shell. This is why POSIX is king. See http://mywiki.wooledge.org/BashFAQ/081 for more ways on avoiding which(1).

Change the homepage of Firefox
This command modifies the preferences file of Firefox that is located in .mozilla/firefox/*.default/prefs.js. It edits the file with sed and the -i option. Then it searches the string "browser.startup.homepage", and the string next to it (second string). Finally, it replaces the second string with the new homepage, that is http://sliceoflinux.com in the example. It doesn't work if you haven't set any homepage.

Create a Multi-Part Archive Without Proprietary Junkware
Leave it to a proprietary software vendor to turn a cheap and easy parlor trick into a selling point. "Hey guys, why don't we turn our _collection of multiple files_ into a *collection of multiple files*!!" Extract the ^above with this: $ cat pics.tar.gz.??? | tar xzv ^extract on any Unix - no need to install junkware! (If you must make proprietary software, at least make it do something *new*) if [ -e windows ]; then use 7-Zip

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