lock_info()
Get information about a PSL process lock.
Syntax
Parameter
Parameter | Definition |
|---|---|
lock_name | name of the lock acquired by the lock() function, or "" (empty string) to return the entire lock table |
separator | single character that separates one list from another list The string returned by the lock_info() function is composed of three lists: number of read/write locks, list of waiting processes, and process Id (PID) oflock_name. The separator character delimits these lists. Default |
separator_2 | character that separates one member of a list from another When a list in the return string contains more than one member, separator_2 delimits each member of the list. For example, if more than one process is waiting for the lock to be lifted, a comma (by default) separates the name of each process. Default |
Description
The lock_info() function gets information about a lock that was acquired by the lock() function (see lock()). If successful, this function returns a string that contains information about the lock. If unsuccessful, it returns the empty string.
If an empty string is used in place of a lock name, a list of all locks is returned.
The return string uses the following format:
number_read,number_write|waiting_processes|lock_pid
Return Value | Description |
|---|---|
number_read | number of processes that are waiting for shared (reader) access under the lock This value and number_write are separated by a comma ( separator ) because they are both members of the same list. |
number_write | number of processes that are waiting for exclusive (writer) access |
waiting_processes | list of processes that are waiting for access Each member of this list is a PID of the waiting process followed by an r or w to indicate the type of lock. For example, 167r indicates that process 167 is waiting for a read lock and 242w indicates process 242 is waiting for a write lock. |
lock_pid | PID of lock_name |