unexpand

Convert spaces to tabs.

• Convert blanks in each file to tabs, writing to standard output:

unexpand {{file}}

• Convert blanks to tabs, reading from standard output:

unexpand

• Convert all blanks, instead of just initial blanks:

unexpand -a {{file}}

• Convert only leading sequences of blanks (overrides -a):

unexpand --first-only {{file}}

• Have tabs a certain number of characters apart, not 8 (enables -a):

unexpand -t {{number}} {{file}}