rik(_at_)netcom(_dot_)com (Rik Kabel) writes:
Assume that the content of a header (for the sake of example,
Subject) has been saved in the variable (again for example,
SUB) as follows:
:0
* ^Subject:[ ]+\/[^ ].*
{ SUB=$MATCH }
What reasons might there be to prefer one over the other of the
following alternative recipes?
:0: # Alternative construction 1
* ^Subject:.*xyz
fileit
:0: # Alternative construction 2
* SUB ?? xyz
fileit
The latter will be faster.
Would the answer be different for the following alternatives?
:0: # Alternative construction 3
* ^Subject:[ ]+xyz$
fileit
:0: # Alternative construction 4
* SUB ?? ^^xyz^^
fileit
No. Given that you've already spent the cycles to locate and extract
the Subject: header, it really doesn't matter what regexp you search
for -- procmail's regexp engine will have less to scan through.
Philip Guenther