Commands by zude (5)

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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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silent/shh - shorthand to make commands really quiet
Sometimes I just want to run a command quietly but all that keyboard shifting makes my fingers hurt. This little function does the job eg.: $ if shh type less; then PAGER=less; fi

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

Localize provenance of current established connections
Sample command to obtain a list of geographic localization for established connections, extracted from netstat. Need geoiplookup command ( part of geoip package under CentOS)

Start an X app remotely
Launch a gui app remotely. In this example smplayer is installed on the remote machine, and movie.avi is in the remote user's home dir. Note that stdout/stderr is still local, so you'll have feedback locally, add '&>/dev/null' to suppress. This is surprisingly not well known (compared to running an X app locally via ssh -X). (NB. if your distro requires ~/.Xauthority file present, then try -fX if you have problems) Resubmitted (and trimmed, thanks sitaram) due to ridiculous voting on previous submission. Fingers crossed, it gets a better rating this time.

Get your external IP address
Request all information about my IP address in json format

enable all bash completions in gentoo

Efficiently print a line deep in a huge log file
Sed stops parsing at the match and so is much more effecient than piping head into tail or similar. Grab a line range using $ sed '999995,1000005!d' < my_massive_file

Get contents from hosts, passwd, groups even if they're in DB/LDAP/other
getent allows to get the contents of several databases in their native file format even if they are not actually in /etc. For example, if you are using a LDAP or a DB to authenticate your users, you won't find their info by catting /etc/passwd, but "getent passwd" will concatenate /etc/passwd to the LDAP/DB.

search for a file in PATH
Also searches for aliases and shell builtins

Command to keep an SSH connection open
This runs the uptime command every 30 seconds to avoid an SSH connection dropping due to inactivity. Granted there are better ways of solving this problem but this is sometimes the right tool for the job.

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