Returns an sha1 hash for a file.
This function returns an 160-bit sha1 hash of a file and can be used to verify the integrity of a file. If the call fails, FALSE is returned.
<?php
print "sha1 hash for log.txt: " . sha1_file("log.txt");
?> sha1 hash for log.txt: 56afe6a19be03c97f49fd18e615e0417302e9a1c An sha1 hash for log.txt is generated and printed.