Xargs takes a newline separated list and maps the list to a command.

    find ./ -name '*.log' | xargs rm

Finds all log files and map them to 'rm' commands. e.g. if it finds system.log and rails.log it will run the command `rm system.log rails.log`.

xargs will automatically do things like break up very long lists into multiple command calls so that it doesn't exceed the maximum number of arguments a command can have.

Other useful things about xargs are '-P <NUM>' which lets you run the same command in parallel. I use this with curl to do ghetto benchmarks.

The next major flag is `-n <NUM>` which changes the number of arguments per command call. e.g. `-n 1` will run the command per argument passed to xargs.

And the last flag I commonly use is `-I {}`. This sets `{}` as a variable which contains the arguments. (This also forces `-n 1`). This is useful for things like:

    find ./ -name '*.log' | xargs -I{} sh -c "if [ -f {}.gz ]; then rm {}; fi"