-sh

What is this?

• trap "cleanup" 0 (2013-08-23)
• pwgen() { LC_CTYPE=C tr -dc 'A-Za-z0-9\`~!@#$%^&*()_+[]{}\|;:<>?,./' </dev/urandom | head -c ${1:-16} | xargs; } (2013-02-22)
• ssh hostA "cat file1" | tee file | ssh hostB "cat <file2" (2013-02-16)
• awk '!_[$0]++' file (2013-02-13)
• <file tr -cd '[:print:]' | tr '[:upper:]' '[:lower:]' | tr -d ' ' | fold -w1 | sort | uniq -c | sort -n (2013-02-12)
• <file tr '[:punct:]' ' ' | tr '[:space:]' '\n' | tr '[:upper:]' '[:lower:]' | egrep '^[a-z]+$' | sort | uniq -c | awk '{print length() " " $2;}'| sort -n (2013-02-10)
• <file tr '[:punct:]' ' ' | tr '[:space:]' '\n' | tr '[:upper:]' '[:lower:]' | egrep '^[a-z]+$' | sort | uniq -c | sort -n (2013-02-09)
• fullname() { echo $(cd $(dirname ${1}) && pwd -P)/$(basename ${1}); } (2013-02-08)
• ls | wc -l (2013-02-07)

I like Unix. I particularly like the Unix Philosophy:

Write programs that do one thing and do it well. Write programs to work together. Write programs to handle text streams, because that is a universal interface.

There are a number of Twitter accounts that post some good command-line fu, but I've found that invariably they end up posting about one interesting nugget in a sea of basic commands. And so I figured I'd give it a try myself and simply post those commands I come across that -- at least to me -- are either non-obvious or of particular interest.

In the interest of keeping readers on their toes (and myself more easily within the restraints of the 140 characters), I've chosen to not post any explanatory details or hashtags etc. Ideally, one would be able to figure out what the command does, if not by inspection, then perhaps with the help of the friendly manual pages.

Should you be interested in more details, I'll be posting a short summary of each tweet linked from this page.

I expect the frequency of tweets to be very low, as I only have so many really interesting commands, and if I want to actually add a summary for each, that also takes time. That is, I'd like to add some value to even a neat command I might find posted somewhere else. You're welcome to send me suggestions at @jschauma, @rtfmsh, or, with a detailed explanation, at jschauma@netmeister.org.

Oh, and one more thing. This is /bin/sh -- well, ash(1), anyway -- not /bin/bash. So there's that.