STREAMS-UX Programmer's Guide (February 2007)

STREAMS Utilities Supported by HP-UX

Appendix B

231

NAME

unfreezestr () – Unfreeze the frozen queue.

SYNOPSIS

#include <sys/stream.h>

void unfreezestr(queue_t *q, pl_t pl);

PARAMETERS

Pointer to a message queue.

The interrupt priority level to be set after unfreezing the stream. (This value is ignored, but

has been retained for portability.)

DESCRIPTION

unfreezestr() unfreezes the queue specified by

. Unfreezing the queue allows the continuation of all

activities that may have been forced to wait while the queue was frozen. This call must only be made by the

caller of freezestr().

The caller freezing the queue by calling freezestr() must also unfreeze the queue by calling unfreezestr()

after the required operations have been performed on the frozen queue.

unfreezestr() is only applicable to the module/drivers configured at the synchronization level

SQLVL_NOSYNC. For modules/drivers configured at any other synchronization level, STREAMS/UX uses a

different mechanism to protect STREAMS/UX queues and the unfreezestr() utility for these

modules/drivers is a no-op provided to make porting code easier.

RETURN VALUES

None

CONSTRAINTS

None