ls -l | wc -l ls: list directory contents -l: list in long format wc: word, line, character, and byte count -l: the number of lines is written to the standard output This command counts the number of listed lines. I find this most useful when I want to quickly see how many logs or records have been generated by a process.
detex my-document.tex | wc -w detex: a filter to strip TeX commands from a .tex file wc: word, line, character, and byte count -w: The number of words in each input file is written to the standard output
git submodule foreach --recursive git reset --hard This command recursively resets all submodules in a git project. This is especially useful for projects with submodules (and maybe even submodules within submodules) when you want to reset your working copy to a completely clean state.
Sometimes Travis CI builds fail due to sporadic timeouts, network errors, etc. While these non-code errors can be quite annoying, Travis CI has a handy Restart build for when these situations occur, but only users with admin privileges have access to this feature.