The CLI tools you need to know
cut
cut takes a delimiter (-d) and splits input on that delimiter (like String.Split() or String.Fields() in many programming languages). You then select which field (list element) you want to output with -f, e.g. f1 for the first field.
If you feed cut more than one line, it will repeat that same operation on all lines.
# echo "this is a space-delimited line" | cut -d " " -f4
space-delimitedTo get friendly names for all users with ‘root’ in their names (on an OS X machine):
# grep root /etc/passwd | cut -d ":" -f5
System Administrator
System Services
CVMS Rootsort
sort does a per-line sorting (alphabetial or numeric).
Reverse-sorting with -r is often useful when dealing with numeric data (-n). You’ll often want -rn together (see “Top X” in the patterns section of this chapter).
The -h flag can be very useful for sorting by human readable output of many other commands, like this:
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