Commands by depesz (36)

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commandlinefu.com is the place to record those command-line gems that you return to again and again. That way others can gain from your CLI wisdom and you from theirs too. All commands can be commented on, discussed and voted up or down.

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Delete all local git branches that have been merged
This checks if the branch has been merged with master and then will delete the ones that have been. Keeps your local git repo nice and clean from all the branches.

draw line separator
Even shorter: $ seq -s '*' 120|tr -d '[0-9]'

Mplayer save stream to file
To save any streaming url content to a file.

Syntax Highlight your Perl code
This uses Text::Highlight to output the specified Perl file with syntax highlighting. A better alternative is my App::perlhl - find it on the CPAN: http://p3rl.org/App::perlhl

Use a var with more text only if it exists
See "Parameter Expansion" in the bash manpage. They refer to this as "Use Alternate Value", but we're including the var in the at alternative.

Print the contents of $VARIABLE, six words at a time
Print out the contents of $VARIABLE, six words per line, ignoring any single or double quotes in the text. Useful when $VARIABLE contains a sentence that changes periodically, and may or may not contain quoted text.

phpinfo from the command line
php -i seems to show default not real

Apply, in parallel, a bc expression to CSV
Define a function that applies bc, the *nix calculator, with the specified expression to all rows of the input CSV. The first column is mapped to {1}, second one to {2}, and so forth. See sample output for an example. This function uses all available cores thanks to GNU Parallel. Requires GNU Parallel

view certificate details

Use socat to emulate an SMTP mail SERVER
Lots of scripts show you how to use socat to send an email to an SMTP server; this command actually emulates an SMTP server! It assumes the client is only sending to one recipient, and it's not at all smart, but it'll capture the email into a log file and the client will stop retrying. I used this to diagnose what emails were being sent by cron and subsequently discarded, but you can use it for all sorts of things.


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