Commands by cfajohnson (19)

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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Are there any words in the English language that use at least half of the alphabet without repeating any letters?
This is the most straightforward approach: first regexp limits dictionary file to words with thirteen or more characters, second regexp discards any words that have a letter repeated. (Bonus challenge: Try doing it in a single regexp!)

Binary difference of two files
Upload/download newer version of any file with less size and high speed. To remake the new file use $bspatch

diff files while disregarding indentation and trailing white space
**NOTE** Tekhne's alternative is much more succinct and its output conforms to the files actual contents rather than with white space removed My command on the other hand uses bash process substitution (and "Minimal" Perl), instead of files, to first remove leading and trailing white space from lines, before diff'ing the streams. Very useful when differences in indentation, such as in programming source code files, may be irrelevant

Kick user

what model of computer I'm using?

ssh batch jobs: query hundreds of hosts with an ssh command
Need to query hundreds of hosts with an ssh command ? Of course you'll have setup keys on all your remote HOSTs. But in the case a key is not present this command will skip that node, proceeding on to the next. -t: Force pseudo-tty allocation. This can be used to execute arbitrary screen-based programs on a remote machine. Also prevents unwanted stty messages being sent to console -q: Quiet mode. -o "BatchMode yes" If set to yes, passphrase/password querying will be disabled. This option is useful in scripts and other batch jobs where no user is present

Update twitter with curl
Same as below, but no quotes are necessary when twitting more than one word

Forwards connections to your port 2000 to the port 22 of a remote host via ssh tunnel

display date of last time a process was started in `date` format
STARTED Mon Oct 18 04:02:01 2010

Suppress output of loud commands you don't want to hear from
Suppresses all output to /dev/null. This could be expanded to check for a -l command line option to log the stderr to a file maybe -l file or -l to log to default quietly.log. I'm finding that I use it more often than one would think.

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