23. Process Substitution (Revision #2)

Piping the  stdout  of a  command into the stdin of another is a  powerful technique. But, what if you need to pipe the stdout of multiple commands? This is where process substitution come s in.

Process substitution feeds the output of a process (or processes) into the stdin of another process.

Template

Command list enclosed within parentheses

>(command_list)

<(command_list)

Process substitution uses /dev/fd/<n> files to send the results of the process(es) within parentheses to another process. ¹

  There is no space between the the " < " or ">" and the parentheses. S pace there would give an error message.