method
flock
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flock(p1)
public
Locks or unlocks a file according to locking_constant (a logical or of the values in the table below). Returns false if File::LOCK_NB is specified and the operation would otherwise have blocked. Not available on all platforms.
Locking constants (in class File):
LOCK_EX | Exclusive lock. Only one process may hold an | exclusive lock for a given file at a time. ----------+------------------------------------------------ LOCK_NB | Don't block when locking. May be combined | with other lock options using logical or. ----------+------------------------------------------------ LOCK_SH | Shared lock. Multiple processes may each hold a | shared lock for a given file at the same time. ----------+------------------------------------------------ LOCK_UN | Unlock.
Example:
File.new("testfile").flock(File::LOCK_UN) #=> 0