Edit report at http://bugs.php.net/bug.php?id=53061&edit=1
ID: 53061 Updated by: cataphr...@php.net Reported by: crrodriguez at opensuse dot org Summary: filesystem functions deal poorly with out of disk space conditions Status: Open Type: Bug Package: Filesystem function related Operating System: *nix PHP Version: 5.3SVN-2010-10-14 (SVN) Block user comment: N New Comment: Well, there's the hint that the return value is smaller than strlen(str_repeat("fail", 1024000)) = 4096000. I'm not sure if adding a warning here is appropriate, we try to avoid warnings in correct scripts so that programmers don't have to use "@" to have notice/warning free code. Even if we consider a disk full an exceptional circumstance that merited breaking this guideline, a warning would be of little use; unless the logs are in a separate filesystems, the warning message would not be able to be logged. So: * We can't return false, because a part of the data may have been written and we need to return how much. * A warning would be of no use in most circumstances. Maybe we could return a false+warning if no data has been written, but it seems dangerous because sometimes programmers would be warned of an out-of-disk-space conditional and other times they wouldn't. Previous Comments: ------------------------------------------------------------------------ [2010-10-15 02:47:11] crrodriguez at opensuse dot org A liltte bit better test case: # dd if=/dev/zero of=/tmp/vfs bs=1024 count=1024 # losetup /dev/loop0 /tmp/vfs # mkfs -t ext2 -m 1 -v /dev/loop0 # mkdir /mnt/vfs # mount -t ext2 /dev/loop0 /mnt/vfs <?php $fp = fopen('/mnt/vfs/foo.txt', 'wb'); var_dump(fwrite($fp, str_repeat("fail", 1024000))); var_dump(fflush($fp)); var_dump(fclose($fp)); ?> int(1003520) bool(true) bool(true) ls -l /mnt/vfs/foo.txt -rw-r--r-- 1 root root 1003520 oct 14 21:43 /mnt/vfs/foo.txt Partial data on disk, no warning or return values hinting the problem. ------------------------------------------------------------------------ [2010-10-14 07:00:13] cataphr...@php.net Why would fflush return false? Nothing was written by fwrite, so the flush is a no-op. ------------------------------------------------------------------------ [2010-10-14 06:35:11] crrodriguez at opensuse dot org Description: ------------ Filesystem functions have IMHO the wrong behaviuor on disk-full conditions Test script: --------------- <?php $fp = fopen('/dev/full', 'wb'); var_dump(fwrite($fp, "fail")); var_dump(fflush($fp)); var_dump(fclose($fp)); Expected result: ---------------- bool(false) and "warning ...No space left on device.. (aka, handle ENOSPC) bool(false) bool(true) Actual result: -------------- int(0) bool(true) bool(true) ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/bug.php?id=53061&edit=1