[TriLUG] bash cmd line processing question

[Paul D. Boyle]

Mike Mueller wrote:
> 
> why does the following command work:
> 
> $kill -SIGHUP `cat /var/run/syslogd.pid`
> 
> why does the following command *not* work:
> 
> $kill -SIGHUP 'cat /var/run/syslogd.pid'

Beacuse the backquotes (`) cause command substitution, i.e. the
shell substitutes the command (and the backquotes) with the
output produced by that command.

The (') is one of the ways to quote strings in shells, and I have
never really understood the difference between " and '.

Paul


-- 
Paul D. Boyle			    |	boyle at laue.chem.ncsu.edu
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