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Locks the mutex.

Component Version macOS Windows Linux Server iOS SDK
Mutex 10.2 ✅ Yes ✅ Yes ✅ Yes ✅ Yes ✅ Yes
MBS( "Mutex.Lock"; Mutex )   More


Parameter Description Example
Mutex The reference number of the mutex. $mutex


Returns OK or error.


Locks the mutex.
Only one application can lock the mutex.
Please call Mutex.Unlock later to unlock the mutex.

To avoid you looking up the FileMaker app, we limit locking to one minute. After that you get a timeout error.


Lock a mutex:

MBS( "Mutex.Lock"; $Mutex )

Lock and unlock:

# lock it
Set Variable [ $r ; Value: MBS( "Mutex.Lock"; $Mutex ) ]
# do something
# finally unlock
Set Variable [ $r ; Value: MBS( "Mutex.Unlock"; $Mutex ) ]

See also

This function checks for a license.

Created 5th April 2020, last changed 5th April 2020

Mutex.List - Mutex.Name