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Search for a process by name
ps and grep is a dangerous combination -- grep tries to match everything on each line (thus the all too common: grep -v grep hack). ps -C doesn't use grep, it uses the process table for an exact match. Thus, you'll get an accurate list with: ps -fC sh rather finding every process with sh somewhere on the line.

easy C shell math calculators
allows simple C shell access to the power of bc - never could figure out how to do the same thing with Bash - that's why I use tcsh most of the time.

bulk rename files with sed, one-liner
Far from my favorite, but works in sh and with an old sed that doesn't support '-E'

Output files without comments or empty lines
Filter comments and empty lines in files. I find this very useful when trying to find what values are actually set in a very long example config file. I often set an alias for it, like : alias nocomment='grep -v "^\($\|#\)"'

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"

Never rewrites a file while copying (or moving)
Allows you to preserve your files when using cp, mv, ln, install or patch. When the target file exists, it will generate a file named XXX.~N~ (N is an auto-incremental number) instead of deleting the target file.

Outputs a 10-digit random number

Clean up poorly named TV shows.
Replace 'SHOWNAME' with the name of the TV show. Add -n to test the command without renaming files. Check the 'sample output'.

Given process ID print its environment variables
Same as previous but without fugly sed =x

Insert a comment on command line for reminder
Comments can be used directly on the command line so I can save in the history a brief description of what command does.


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