Commands by jaymcjay (0)

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swap stdout and stderr
Possible use, to filter something in stderr: (/usr/bin/$COMMAND $PARAM 3>&1 1>&2 2>&3 | grep -v $uninteresting_error ) 3>&1 1>&2 2>&3

check open ports (both ipv4 and ipv6)
While `lsof` will work, why not use the tool designed explicitly for this job? (If not run as root, you will only see the names of PID you own)

find out how many days since given date
You can also do this for seconds, minutes, hours, etc... Can't use dates before the epoch, though.

ignore .DS_Store forever in GIT
With a couple of little commands, you?ll be able to ignore the .DS_Store files forever from your git repositories on mac! The following command will add the .gitignore file to the git configuration git config --global core.excludesfile ~/.gitignore then, the following, will add the .DS_Store to the list echo .DS_Store >> ~/.gitignore

create an incremental backup of a directory using hard links
dname is a directory named something like 20090803 for Aug 3, 2009. lastbackup is a soft link to the last backup made - say 20090802. $folder is the folder being backed up. Because this uses hard linking, files that already exist and haven't changed take up almost no space yet each date directory has a kind of "snapshot" of that day's files. Naturally, lastbackup needs to be updated after this operation. I must say that I can't take credit for this gem; I picked it up from somewhere on the net so long ago I don't remember where from anymore. Ah, well... Systems that are only somewhat slicker than this costs hundreds or even thousands of dollars - but we're HACKERS! We don't need no steenkin' commercial software... :)

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

start vim in diff mode
vim will open both files side by side and show colored diffs

Analyze awk fields
Breaks down and numbers each line and it's fields. This is really useful when you are going to parse something with awk but aren't sure exactly where to start.

Arch Linux: Always install software without asking
Adding this alias to ~/.bashrc or, better yet, the system-wide /etc/bash.bashrc (as in my setup) will make it possible to not only run pacman as any user without needing to prepend sudo but will also ensure that it always assumes that the user knows what he or she is doing. Not the best thing for large multi-user enterprise setups at all to say the least, but for home (desktop) use, this is a fantastic time-saver.

A function to find the newest file in a directory

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