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PdCreateOffscreenLock()

Create a lock for an offscreen context

Synopsis:

int PdCreateOffscreenLock(
       PdOffscreenContext_t *osc,
       PdOSCCreateLockParams_t *params );

Arguments:

osc

A pointer to the PdOffscreenContext_t structure for the offscreen context.

params

A pointer to a PdOSCCreateLockParams_t structure that defines the parameters for the lock; see below.

Library:

ph

Description:

This function creates an offscreen lock in an offscreen context.

This function doesn't lock the offscreen context; to do that, call PdLockOffscreen().

The PdOSCCreateLockParams_t structure includes the following members:

uint32_t flags

Flags, including:

• Pg_OSC_LOCK_SIG -- register a signal to be dropped if a request is made to remove the offscreen context while it's locked.

int sig

The signal to drop on the current hard locking process if the context needs to be destroyed.

This signal is used only if you set Pg_OSC_LOCK_SIG in the flags member.

You can't lock the primary display unless the application is in direct mode.

Returns:

EOK

The lock was successfully created.

Pg_OSC_LOCK_ALREADY_CREATED

The lock has already been created for this offscreen context.

Pg_OSC_CREATE_LOCK_FAILED

The lock couldn't be created. The most likely reason is that io-graphics is running remotely.

Classification:

Photon

See also:

PdDestroyOffscreenLock(), PdGetOffscreenContextPtr(), PdIsOffscreenLocked(), PdLockOffscreen(), PdUnlockOffscreen()

"Offscreen locks" in the Raw Drawing and Animation chapter of the Photon Programmer's Guide