I recently had reason to run file(1) (file-5.03 on FreeBSD 8-stable) on a large number of files and felt the performance wasn't up to par. When I investigated further, I found that about 95% of the runtime related to the two regex's to recognize REXX files:
# OS/2 batch files are REXX. the second regex is a bit generic, oh well
# the matched commands seem to be common in REXX and uncommon elsewhere
100 regex/c =^[\ \t]{0,10}call[\ \t]{1,10}rxfunc OS/2 REXX batch file text
100 regex/c =^[\ \t]{0,10}say\ ['"] OS/2 REXX batch file text
Since REXX files are not present in my environment, I can avoid the
issue by just commenting out the offending lines. Someone with more
expertise in magic(5) might be able to suggest a better fix.
--
Peter Jeremy
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