Twas brillig at 15:58:10 12.04.2010 UTC+02 when tom@dbservice.com did gyre and gimble:

 TC> In 4fd9ea0 (guess From address from Received headers, 2010-04-06) you introduced
 TC> strcasestr, which is not portable, see 82e47ec (notmuch reply: Use strstr
 TC> instead of strcasestr for portability., 2010-02-04).

 TC> Is strcasestr really necessary there or can it be replaced with strstr?

strcasecmp is POSIX.1-2001.

If you know any OS which does not have it, add a new file to compat/ subdir.

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