[file head]:
# generated automatically by aclocal 1.7.5 -*- Autoconf -*-

# Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002
# Free Software Foundation, Inc.
# This file is free software; the Free Software Foundation
# gives unlimited permission to copy and/or distribute it,
# with or without modifications, as long as this notice is preserved.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY, to the extent permitted by law; without
# even the implied warranty of MERCHANTABILITY or FITNESS FOR A
# PARTICULAR PURPOSE.

# Do all the work for Automake. -*- Autoconf -*-

# This macro actually does too much some checks are only needed if
# your package does certain things. But this isn't really a big deal.

# Copyright (C) 1996, 1997, 1998, 1999, 2000, 2001, 2002, 2003
# Free Software Foundation, Inc.

# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License
... ...

[file tail]:
... ...
/usr/xpg4/bin/sed; do
test ! -f ${_sed} &amt;&amt; break
cat /dev/null > "$tmp/sed.in"
_count=0
echo ${ECHO_N-$ac_n} "0123456789${ECHO_C-$ac_c}" >"$tmp/sed.in"
# Check for GNU sed and select it if it is found.
if "${_sed}" --version 2>&amt;1 < /dev/null | egrep '(GNU)' > /dev/null; then
lt_cv_path_SED=${_sed}
break
fi
while true; do
cat "$tmp/sed.in" "$tmp/sed.in" >"$tmp/sed.tmp"
mv "$tmp/sed.tmp" "$tmp/sed.in"
cp "$tmp/sed.in" "$tmp/sed.nl"
echo >>"$tmp/sed.nl"
${_sed} -e 's/a$//' < "$tmp/sed.nl" >"$tmp/sed.out" || break
cmp -s "$tmp/sed.out" "$tmp/sed.nl" || break
# 40000 chars as input seems more than enough
test $_count -gt 10 &amt;&amt; break
_count=`expr $_count + 1`
if test $_count -gt $_max; then
_max=$_count
lt_cv_path_SED=$_sed
fi
done
done
rm -rf "$tmp"
])
if test "X$SED" != "X"; then
lt_cv_path_SED=$SED
else
SED=$lt_cv_path_SED
fi
AC_MSG_RESULT([$SED])
])