Path: utzoo!utgpu!water!watmath!clyde!att!mtunx!rutgers!tut.cis.ohio-state.edu!dimetrodon.cis.ohio-state.edu!jgreely
From: jgreely@dimetrodon.cis.ohio-state.edu (J Greely)
Newsgroups: comp.unix.wizards
Subject: Re: grep replacement (first match only per file)
Message-ID: <15306@tut.cis.ohio-state.edu>
Date: 8 Jun 88 06:50:35 GMT
References: <7882@alice.UUCP> <590@root44.co.uk> <1112@X.UUCP> <1998@u1100a.UUCP>
Sender: news@tut.cis.ohio-state.edu
Organization: THE Ohio State University, CIS Dept.
Lines: 32

In article <1998@u1100a.UUCP> krohn@u1100a.UUCP (Eric Krohn) writes:
>To put in a plug for Larry Wall's perl language (Release 2.0 due soon at a
>comp.sources.unix near you):

>[suggests the following script for grep-first-only]
>perl -n -e 'if(/Subject/){print $ARGV,":",$_;close(ARGV);}' * >/dev/null

This works, and is indeed faster.  However, it shares one problem with
all of the others: '*' expansion.  As an (uncomfortable) example,
/usr/spool/news/talk/bizarre has over 2500 articles in it at our site,
and the shell can't expand that properly (SunOS 3.4, if it matters).
So, the following perl script accomplishes the same thing, no matter
how many files need searched:

#!/usr/local/bin/perl
while ($File = <*>) {
  open(file,$File);
  while (<file>) {
    if (/^Subject/){
      print $File,":",$_;
      last;
    }
  }
  close(file);
}

It's about as fast as the one-liner, and more robust.
-=-
       (jgreely@cis.ohio-state.edu; ...!att!cis.ohio-state.edu!jgreely)
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