XtAllocateGC(3Xt) XT FUNCTIONS XtAllocateGC(3Xt)
NAME
XtAllocateGC - obtain a sharable GC with modifiable fields
SYNTAX
GC XtAllocateGC(Widget w, Cardinal depth, XtGCMask
value_mask, XGCValues *values, XtGCMask dynamic_mask,
XtGCMask unused_mask);
ARGUMENTS
values Specifies the actual values for this GC.
value_mask
Specifies which fields of the values are speci-
fied.
w Specifies the widget.
depth Specifies the depth for which the returned GC is
valid, or 0.
dynamic_mask
Specifies the fields of the GC that will be modi-
fied by the caller.
unused_mask
Specifies the fields of the GC that will not be
needed by the caller.
DESCRIPTION
The XtAllocateGC function returns a sharable GC that may be
modified by the client. The screen field of the specified
widget or of the nearest widget ancestor of the specified
object and the specified depth argument supply the root and
drawable depths for which the GC is to be valid. If depth is
zero the depth is taken from the depth field of the speci-
fied widget or of the nearest widget ancestor of the speci-
fied object.
The value_mask argument specifies the fields of the GC that
will be initialized with the respective members of the
values structure. The dynamic_mask argument specifies fields
that the caller intends to modify during program execution.
The caller must ensure that the corresponding GC field is
sdet prior to each use of the GC. The unused_mask argument
specifies fields of the GC that are of no interest to the
caller. The caller may make no assumptions about the con-
tents of any fields specified in unused_mask. The caller may
assume that at all times all fields not specified in either
dynamic_mask or unused_mask have their default value if not
specified in value_mask or the value specified by values. If
a field is specified in both value_mask and dynamic_mask,
the effect is as if it were specified only in dynamic_mask
XFree86 Version 4.5.0 1
XtAllocateGC(3Xt) XT FUNCTIONS XtAllocateGC(3Xt)
and then immediately set to the value in values. If a field
is set in unused_mask and also in either value_mask or
dynamic_mask, the specification in unused_mask is ignored.
XtAllocateGC tries to minimize the number of unique GCs
created by comparing the arguments with those of previous
calls and returning an existing GC when there are no con-
flicts. XtAllocateGC may modify and return an existing GC if
it was allocated with a nonzero unused_mask.
SEE ALSO
XtGetGC
X Toolkit Intrinsics - C Language Interface
Xlib - C Language X Interface
XFree86 Version 4.5.0 2