Commands by jbuchbinder (2)

What's this? 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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how to export a table in .csv file
Exports the result of query in a csv file

Vectorize xkcd strips
Uses ImageMagick and potrace to vectorize the input image, with parameters optimized for xkcd-like pictures.

raw MySQL output to use in pipes
-N removes header -s removes separator chars -r raw output After using these options, the MySQL ouptut can be used with pipes very easily

Functions to display, save and restore $IFS
You can display, save and restore the value of $IFS using conventional Bash commands, but these functions, which you can add to your ~/.bashrc file make it really easy. To display $IFS use the function ifs shown above. In the sample output, you can see that it displays the characters and their hexadecimal equivalent. This function saves it in a variable called $saveIFS: $ sifs () { saveIFS=$IFS; } Use this function to restore it $ rifs () { IFS=$saveIFS; } Add this line in your ~/.bashrc file to save a readonly copy of $IFS: $ declare -r roIFS=$IFS Use this function to restore that one to $IFS $ rrifs () { IFS=$roIFS; }

Harder, Faster, Stronger SSH clients
We force IPv4, compress the stream, specify the cypher stream to be Blowfish. I suppose you could use aes256-ctr as well for cypher spec. I'm of course leaving out things like master control sessions and such as that may not be available on your shell although that would speed things up as well.

detect partitions
`blkid` is an interface to libuuid - it can read Device Mapper, EVMS, LVM, MD, and regular block devices. -c /dev/null - Do not use cached output from /etc/ or /etc/blkid/ (RHEL) -i - Display I/O Limits (aka I/O topology) information (not available in RHEL) -p - Low-level superblock probing mode (not available in RHEL)

list files recursively by size

Search apache virtual host by pattern
Outputs contents of virtual hosts containing PATTERN. Particularly useful for pefrorming complex searches. E.g. search for docroot of $ sed -n '/^[^#]*

Empty a file
The downside of output redirection is that you need permissions. So something like $ > file won't play nicely w/ sudo. You'd need to do something like $ bash -c '> file' instead, you could go w/ $ sudo truncate -s0 file

Find usb device in realtime
Using this command you can track a moment when usb device was attached.

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