[TUHS] Cryptic Unix Commands

Norman Wilson norman at oclsc.org
Thu Sep 6 01:04:41 AEST 2018

Ron Natalie:

  I use the numbers but I think it stems from the days when kill didn't take
  the names.    It's easier for me to remember -1 and -9 than to remember what
  the mnemonics are.


Me too.  And not just the kill command; the (real) shell's
trap command too.

It's all just muscle memory, not a desire to save keystrokes.

On the rare occasions when I need to send a post-modern signal
like SIGSTOP or SIGCONT, I use the name.

As an aside, why do modern kill and sh accept only the
abbreviated form of the signal name, not the full name;
e.g. kill -STOP is OK, kill -SIGSTOP an error?  When we
taught kill about that sometime in (I think) the 9th Edition
era at Research, we allowed either form.  I think it was
Doug who insisted on it, and he was right.

All this applies to shell commands, not to programs.
It is just plain wrong to code
	kill(9, pid)
in C.

Norman Wilson
Toronto ON

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