NAME

buffer_mode − set buffering mode for output primitives. 

SYNOPSIS

C Syntax:

void buffer_mode(fildes,on);
int fildes,on;

FORTRAN77 Syntax:

subroutine buffer_mode(fildes,on)
integer*4 fildes,on

Pascal Syntax:

procedure buffer_mode(fildes,on;integer);

DESCRIPTION

Input Parameters

fildes Integer file descriptor returned by gopen when an I/O path to a graphic device is opened. 

on If on = TRUE, buffering mode is enabled;
If on = FALSE, buffering mode is disabled;

Discussion

Buffer_mode is used to enable or disable buffering of output data for graphic output primitives.  Typically, device drivers accumulate output primitives in an output buffer, then, when the buffer is full or a make_picture_current is performed, the device is locked to prevent other processes from interfering, the buffer is processed, then the device is unlocked.  With buffering disabled, make_picture_current is called automatically after every Starbase output primitive procedure.  The overhead involved in locking and unlocking the device can substantially impair system performance when buffering is disabled.  A more efficient way to ensure an updated display is to invoke make_picture_current after a group of primitives have been processed.  Disabling buffering is sometimes helpful when debugging a program that uses Starbase routines. 

DEFAULTS

Buffering: on (TRUE). 

SEE ALSO

Make_picture_current(3G)

Hewlett-Packard Company  —  HP-UX Release 9.0: August 1992