XChangeGC(display, gc, valuemask, values)
      Display *display;
      GC gc;
      unsigned long valuemask;
      XGCValues *values;


display Specifies the connection to the X server.
gc Specifies the GC.
valuemask Specifies which components in the GC are to be changed using information in the specified values structure. This argument is the bitwise inclusive OR of zero or more of the valid GC component mask bits.
values Specifies any values as specified by the valuemask.


The XChangeGC() function changes the components specified by valuemask for the specified GC. The values argument contains the values to be set. The values and restrictions are the same as for XCreateGC(). Changing the clip-mask overrides any previous XSetClipRectangles() request on the context. Changing the dash-offset or dash-list overrides any previous XSetDashes() request on the context. The order in which components are verified and altered is server-dependent. If an error is generated, a subset of the components may have been altered.

XChangeGC() can generate BadAlloc , BadFont , BadGC , BadMatch , BadPixmap , and BadValue errors.


BadAlloc The server failed to allocate the requested source or server memory.
BadFont A value for a font argument does not name a defined font (or, in some cases, GContext).
BadGC A value for a GContext argument does not name a defined GContext.
BadMatch An InputOnly window is used as a Drawable.
BadMatch Some argument or pair of arguments has the correct type and range but fails to match in some other way required by the request.
BadPixmap A value for a Pixmap argument does not name a defined Pixmap.
BadValue Some numeric value falls outside the range of values accepted by the request. Unless a specific range is specified for an argument, the full range defined by the argument's type is accepted. Any argument defined as a set of alternatives can generate this error.

See also

AllPlanes(), XCopyArea(), XCopyGC(), XCreateGC(), XCreateRegion(), XDrawArc(), XDrawLine(), XDrawRectangle(), XDrawText(), XFillRectangle(), XFreeGC(), XGContextFromGC(), XGetGCValues(), XQueryBestSize(), XSetArcMode(), XSetClipOrigin(), "Manipulating Graphics Context/State".
Christophe Tronche, [email protected]