XtAllocateGC(3Xt)

     NAME
          XtAllocateGC - obtain a sharable GC with modifiable fields

     SYNTAX
          GC XtAllocateGC(w, depth, value_mask, values, dynamic_mask,
          unused_mask)
                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
                    specified.

          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
                    modified 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
          specified widget or of the nearest widget ancestor of the
          specified 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
          contents 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 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
          conflicts.  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