gslock(3g) — AIX PS/2 1.2.1



GSLOCK(3g,L)                AIX Technical Reference                GSLOCK(3g,L)



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gslock



PURPOSE

Postpones signal processing.

C SYNTAX

int gslock_ ( )

FORTRAN SYNTAX

INTEGER function gslock ( )

PASCAL SYNTAX

FUNCTION gslock_ ( ): INTEGER [PUBLIC];

DESCRIPTION

The gslock subroutine causes the GSL not to acknowledge the SIGRETRACT signal,
if it occurs, until the application requests resumption of the signal handling
with the gsunlk subroutine.  This permits the application to access the display
frame buffer directly.

If the virtual terminal is inactive when the application calls gslock and the
GSL has been instructed to save the frame buffer when the virtual terminal
becomes inactive, gslock suspends the application until the virtual terminal
becomes active and then returns a successful return code.  If the GSL has been
instructed not to save the frame buffer, gslock returns the GS_INAC return code
immediately.  The application must not access the display frame when GS_INAC is
returned.

Note:  If SIGRETRACT signal processing is suspended for more than 30 seconds,
       it is possible that a generated SIGRETRACT signal may be suspended long
       enough for the SIGKILL signal to occur, terminating the application
       process.

RETURN VALUE

GS_SUCC  Virtual terminal active, safe to write to frame buffer.
GS_INAC  Virtual terminal inactive.










Processed November 7, 1990       GSLOCK(3g,L)                                 1
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