Manual Pages for UNIX Operating System command usage for man XShmQueryExtension

X FUNCTIONS                                           XShm(3xext)



NAME
     XShmQueryExtension,   XShmQueryVersion,    XShmPixmapFormat,
     XShmAttach,    XShmDetach   XShmCreateImage,   XShmPutImage,
     XShmGetImage, XShmCreatePixmap, XShmGetEventBase - X  Shared
     Memory extension functions

SYNTAX
     cc [ flag... ] file... -lXext [ library... ]

     #include 
     #include 
     #include 
     #include 

     Bool XShmQueryExtension(
          Display *display);

     Bool XShmQueryVersion(
          Display *display;
          int *major, *minor;
          Bool *pixmaps);

     Status XShmPixmapFormat(
          Display *display);

     Status XShmAttach(
          Display *display;
          XShmSegmentInfo *shminfo);

     Status XShmDetach(
          Display *display;
          XShmSegmentInfo *shminfo);


     XImage *XShmCreateImage (
          Display *display;
          Visual *visual;
          unsigned int depth;
          int format;
          char *data;
          XShmSegmentInfo *shminfo;
          unsigned int width, height);

     Status XShmPutImage(
          Display *display;
          Drawable d;
          GC gc;
          XImage *image;
          int src_x, src_y, dest_x, dest_y;
          unsigned int width, height;
          bool send_event);




X Version 11       Last change: libXext 1.1.2                   1






X FUNCTIONS                                           XShm(3xext)



     Status XShmGetImage (
          Display *display;
          Drawable d;
          XImage *image;
          int x, y;
          unsigned long plane_mask);

     Pixmap XShmCreatePixmap(
             Display *display;
             Drawable d;
             char *data;
          XShmSegmentInfo *shminfo;
          unsigned int width, height, depth);

     Status XShmGetEventBase(
          Display *display);

STRUCTURES
     Events:
     typedef struct {
         int type;               /* of event */
         unsigned long serial;   /* # of last request processed by server*/
         Bool send_event;        /* true if this came from a SendEvent request*/
         Display *display;       /* Display the event was read from */
         Drawable drawable;      /* drawable of request */
         int major_code;         /* ShmReqCode */
         int minor_code;         /* X_ShmPutImage */
         ShmSeg shmseg;          /* the ShmSeg used in the request*/
         unsigned long offset;   /* the offset into ShmSeg used in the request*/
     } XShmCompletionEvent;

     a structure of type XShmSegmentInfo :

     typedef struct {
         ShmSeg shmseg;      /* resource id */
         int shmid;          /* kernel id */
         char *shmaddr;      /* address in client */
         Bool readOnly;      /* how the server should attach it */
     } XShmSegmentInfo;


DESCRIPTION
     XShmQueryExtension checks to see if the shared memory exten-
     sions are available for the specified display.

     XShmQueryVersion returns the version numbers of  the  exten-
     sion  implementation. Shared memory pixmaps are supported if
     the pixmaps argument returns true.

     XShmAttach tells the server to attach to your shared  memory
     segment.  If  all goes well, you will get a non-zero status,
     back and your XImage is ready for use.



X Version 11       Last change: libXext 1.1.2                   2






X FUNCTIONS                                           XShm(3xext)



     XShmDetach tells the  server  to  detach  from  your  shared
     memory segment.

     XShmPutImage combines an image in memory with a shape of the
     specified  drawable.  If  XYBitmap format is used, the depth
     must be one, or a ``BadMatch'' error results. The foreground
     pixel  in  the GC defines the source for the one bits in the
     image, and the background pixel defines the source  for  the
     zero  bits.  For  XYPixmap and ZPixmap, the depth must match
     the depth of the drawable, or a ``BadMatch'' error results.

     XShmGetImage reads image data into a  shared  memory  XImage
     where  display  is  the display of interest, drawable is the
     source drawable, image is the destination XImage,  x  and  y
     are  offsets  within  the  drawable,  and plane_mask defines
     which planes are to be read.

     XShmCreateImage allocates the memory needed  for  an  XImage
     structure  for  the  specified display but does not allocate
     space for the image itself.

     XShmPixmapFormat gets the format for  the  server.  If  your
     application  can  deal with the server pixmap data format, a
     shared memory segment and shminfo structure are created.

     XShmCreatePixmap points to a pixmap which you can manipulate
     in all of the usual ways, with the added bonus of being able
     to edit its contents directly through the shared memory seg-
     ment.

     XShmGetEventBase gets the completion event value.

SEE ALSO
     MIT-SHM - The MIT Shared Memory Extension


ATTRIBUTES
     See attributes(5) for descriptions of the  following  attri-
     butes:

     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    |_____________________________|_____________________________|
    | Availability                | x11/library/libxext         |
    |_____________________________|_____________________________|
    | Interface Stability         | Committed                   |
    |_____________________________|_____________________________|
    | MT-Level                    | See XInitThreads(3X11)      |
    |_____________________________|_____________________________|






X Version 11       Last change: libXext 1.1.2                   3