Is it recommended to use shell :null command on supposedly portable scripts? Does it handle csh, zsh, tcsh and any shell that may exist there?
:
Yes. This is the standard zero utility. Link: http://pubs.opengroup.org/onlinepubs/000095399/utilities/colon.html
, : Thompson shell - it Unix V6 1975 . , , PATH, stderr 2> cd ( chdir).
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: goto. goto , : , . Bourne shell, Bourne/POSIX, , goto, , : no-op ( Unix V7).
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