On 5/27/21 11:20 AM, Andreas Schwab wrote:
On Mai 27 2021, Chet Ramey wrote:
On 5/26/21 9:55 PM, Dale R. Worley wrote:
$ ! ! [ 1 -eq 1 ]; echo $?
0
That last one isn't defined by the manual page. I'm surprised you don't
get a syntax error.
It's clearly valid.
According to the POSIX grammar, a pipeline can only be a pipe_sequence
optionally preceded by a single Bang. If you want another Bang the
pipe_sequnce needs to be either a subshell or a brace_group.
True, but bash accepts it. (So do ksh and mksh; dash and yash do not.)
--
``The lyf so short, the craft so long to lerne.'' - Chaucer
``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU c...@case.edu http://tiswww.cwru.edu/~chet/
