NAME

XCreateGC, XCopyGC, XChangeGC, XFreeGC, XGContextFromGC - create or free graphics contexts

SYNTAX

GC XCreateGC(display, d, valuemask, values)
      Display *display;
      Drawable d;
      unsigned long valuemask;
      XGCValues *values;

XCopyGC(display, src, valuemask, dest)
      Display *display;
      GC src, dest;
      unsigned long valuemask;

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

XFreeGC(display, gc)
      Display *display;
      GC gc;

GContext XGContextFromGC(gc)
      GC gc;

ARGUMENTS

d         Specifies the drawable.

dest      Specifies the destination GC.

display   Specifies the connection to the XWIN server.

gc        Specifies the GC.

src       Specifies the components of the source GC.

valuemask Specifies which components in the GC are to be
          set, copied, or changed . This argument is the
          bitwise inclusive OR of one or more of the valid
          GC component mask bits.

values    Specifies any values as specified by the

valuemask.

DESCRIPTION

     The XCreateGC function creates a graphics context and
     returns a GC.  The GC can be used with any destination draw-
     able having the same root and depth as the specified

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     drawable.  Use with other drawables results in a BadMatch
     error.

     XCreateGC can generate BadAlloc, BadDrawable, BadFont, Bad-
     Match, BadPixmap, and BadValue errors.

     The XCopyGC function copies the specified components from
     the source GC to the destination GC.  The source and desti-
     nation GCs must have the same root and depth, or a BadMatch
     error results.  The valuemask specifies which component to
     copy, as for XCreateGC.

XCopyGC can generate BadAlloc, BadGC, and BadMatch errors.

The XChangeGC function changes the components specified by
valuemask for the specified GC.  The values argument con-
tains 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 com-
ponents 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.

The XFreeGC function destroys the specified GC as well as
all the associated storage.

XFreeGC can generate a BadGC error.

DIAGNOSTICS

BadAlloc  The server failed to allocate the requested

resource or server memory.

     BadDrawable
               A value for a Drawable argument does not name a
               defined Window or Pixmap.

     BadFont   A value for a Font or GContext argument does not
               name a defined Font.

     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.

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     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 gen-
          erate this error.

SEE ALSO

     XQueryBestSize(3X11),
     XSetArcMode(3X11),
     XSetClipOrigin(3X11),
     XSetFillStyle(3X11),
     XSetFont(3X11),
     XSetLineAttributes(3X11),
     XSetState(3X11),
     XSetTile(3X11)
     Xlib - C Language X Interface

XWIN 3.0               Last change: 9/1/88                 .ie t

XWIN 3.0               Last change: 9/1/88                 .ie t