Locking: libmount Reference Manual

Locking

Locking — locking methods for utab or another libmount files

struct

Since v2.39 libmount does nto support classic mtab locking. Now all is based on flock only.

void
mnt_free_lock (struct libmnt_lock *ml);

Deallocates mnt_lock.

struct libmnt_lock handler

int
mnt_lock_file (struct libmnt_lock *ml);

Creates a lock file.

Note that when the lock is used by mnt_update_table() interface then libmount uses flock() for private library file /run/mount/utab.

pointer to struct libmnt_lock instance

0 on success or negative number in case of error (-ETIMEOUT is case of stale lock file).

struct libmnt_lock *
mnt_new_lock (const char *datafile,
              pid_t id);

datafile	the file that should be covered by the lock
id	ignored by library

newly allocated lock handler or NULL on case of error.

void
mnt_unlock_file (struct libmnt_lock *ml);

Unlocks the file. The function could be called independently of the lock status (for example from exit(3)).

lock struct

int
mnt_lock_block_signals (struct libmnt_lock *ml,
                        int enable);

Block/unblock signals when the lock is locked, the signals are not blocked by default.

ml	struct libmnt_lock handler
enable	TRUE/FALSE

<0 on error, 0 on success.

struct libmnt_lock;

Stores information about the locked file