============================== AUXILIARY PROGRAMS FOR TESTING ============================== Not everything a test script can do is easily done within a test script; sometimes it makes a lot more sense to write auxiliary program in C and have the test script call them. Auxiliary commands can be found in the src/ directory and in other packages. Tests wanting to use an auxiliary program found in the src/ directory should note the dependency with: _require_test_program "" Contents: - af_unix -- Create an AF_UNIX socket - dmerror -- fault injection block device control - fsync-err -- tests fsync error reporting after failed writeback - log-writes/replay-log -- Replay log from device mapper log-writes target - open_by_handle -- open_by_handle_at syscall exercise - stat_test -- statx syscall exercise - t_dir_type -- print directory entries and their file type - xfs_io -- General I/O operation exercise ================== QUICK DESCRIPTIONS ================== af_unix The af_unix program creates an AF_UNIX socket at the given location. dmerror dmerror is a program for creating, destroying and controlling a fault injection device. The device can be set up as initially working and then flip to throwing errors for testing purposes. fsync-err Specialized program for testing how the kernel reports errors that occur during writeback. Works in conjunction with the dmerror script in tools/ to write data to a device, and then force it to fail writeback and test that errors are reported during fsync and cleared afterward. log-writes/replay-log Specialized program for replaying a write log that was recorded by device mapper log-writes target. The tools is used to perform crash consistency tests, allowing to run an arbitrary check tool (fsck) at specified checkpoints in the write log. open_by_handle The open_by_handle program exercises the open_by_handle_at() system call. It can check if file handles are valid or stale after certain filesystem operations. See also: _require_exportfs stat_test The stat_test program is primarily designed to exercise the statx() system call. It can check statx() against fstatat() and it can compare and check various file attributes. See also: _require_statx t_dir_type The t_dir_type program exercises the getdents64() system call. It prints directory entry names returned from getdents64() and thier d_type, optionally filtered by type or by inode number. xfs_io The xfs_io program can be found in the xfsprogs package and can be used to perform sequences of I/O commands, though it is limited to what it can do on open files. xfs_io is a debugging tool that is aimed at examining regular file I/O paths rather than a raw XFS volume itself. These code paths include not only the obvious read/write/mmap interfaces for manipulating files, but also cover all of the XFS extensions (such as space preallocation, additional inode flags, etc). Most of its commands can also be used with other filesystems. See also: _require_xfs_io_command