First, let me thank those who replied to my query,
for it helps me to progress in what I want to achieve.
`David W. Tamkin' wrote
Another matter to consider is what should happen if there are spaces or tabs
in the value of $FOUND. Perhaps it should be
RESULT=| myprogram "$FOUND" # in Philip's suggestion, or
{ RESULT = `myprogram "$FOUND" } # in Ed's
That might be especially important if, for some reason, $FOUND contains only
spaces. Alternatively, you could change the condition to require that
$FOUND
have at least one character that is not a space, a tab, nor a newline:
* FOUND ?? [^ ]
Actually, when I used what was suggested in earlier posts,
namely to match FOUND against `.', it failed. I mean, somehow
even when FOUND was empty, FOUND ?? . was true. I solved this
by matching FOUND against `..'. For me, this is not a problem
because I will always ensure that in the final rules something
significant will be more than a character long.
I will try the other suggestions, thanks.
Denis Roegel