defined, and if HAVE_CONFIG_H isn't defined, define
MAIL_USE_POP always (so that this file can be included in
other programs besides emacs).
Only declare h_errno if HAVE_H_ERRNO isn't defined or
HAVE_CONFIG_H isn't defined.
(find_crlf, getline): Instead of using strstr, use a
custom function for finding CRLF.
(my_strstr): Function deleted.