Commands by unixmonkey1907 (1)

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write the output of a command to /var/log/user.log... each line will contain $USER, making this easy to grep for.
This command is useful if you want to copy the output of a series of commands to a file, for example if you want to pastebin the output from 'uname -a', 'lspci -vvv' and 'lsmod' for video driver trouble-shooting on your favorite Linux forum. 'log' takes all the following arguments as a command to execute, with STDOUT sent to /var/log/user.log. The command is echoed to the log before it is executed. The advantages of using logger (as opposed to appending output from commands to a file) are 1) commands are always appended to the logs... you don't have to worry about clobbering your log file accidentally by using '>' rather than '>>' 2) logs are automatically cleaned up by logrotate. The following functions allow you to mark the start and end of a section of /var/log/user.log. $ startlog() { export LOGMARK=$(date +%Y.%m.%d_%H:%M:%S); echo "$LOGMARK.START" | logger -t $USER; } then $ endlog() { echo "$LOGMARK.END" | logger -t $USER; } printlog will print all lines between $LOGMARK.START and $LOGMARK.END, removing everything that is prepended to each line by logger. $ printlog() { sudo sed -n -e "/$LOGMARK.START/,/$LOGMARK.END/p" /var/log/user.log| sed "s/.*$USER: //"; } The following command should dump just about all the information that you could possibly want about your linux configuration into the clipboard. $ startlog; for cmd in 'uname -a' 'cat /etc/issue' 'dmesg' 'lsusb' 'lspci' 'sudo lshw' 'lsmod'; do log $cmd; done; endlog; printlog | xsel --clipboard This is ready for a trip to http://pastebin.com/, and you don't have to worry about leaving temporary files lying around cluttering up $HOME. Caveats: I'm sure that startlog, endlog, and printlog could use some cleanup and error checking... there are unchecked dependencies between printlog and endlog, as well as between endlog and startlog. It might be useful for 'log' to send stderr to logger as well.

Update all packages installed via homebrew
As of March 7, 2012: $ brew update - downloads upgraded formulas $ brew upgrade [FORMULA...] - upgrades the specified formulas $ brew outdated - lists outdated installations Note updating all packages may take an excruciatingly long time. You might consider a discriminating approach: run `brew outdated` and select specific packages needing an upgrade. For more information see homebrew's git repository: https://github.com/mxcl/homebrew

pretend to be busy in office to enjoy a cup of coffee
This will turn it in an infinite loop and also shows random words from a file, so it won't be the same each time and also not just a number.

add all files not under version control to repository
With the force options the same results can be achieved

delete PBS jobs based on strings from qstat output

Get the header of a website

Retrieve "last modified" timestamp of web resource in UTC seconds
This command line assumes that "${url}" is the URL of the web resource. It can be useful to check the "freshness" of a download URL before a GET request.

sed : using colons as separators instead of forward slashes
Having to escape forwardslashes when using sed can be a pain. However, it's possible to instead of using / as the separator to use : . I found this by trying to substitute $PWD into my pattern, like so $ sed "s/~.*/$PWD/" file.txt Of course, $PWD will expand to a character string that begins with a / , which will make sed spit out an error such as "sed: -e expression #1, char 8: unknown option to `s'". So simply changing it to $ sed "s:~.*:$PWD:" file.txt did the trick.

Delete all non-printing characters from a file
tr has some predefined sets of characters that are more convenient to use than characters codes

add all files not under version control to repository
checks which files are not under version control, fetches the names and runs them through "svn add". WARNING: doesn't work with white spaces.


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