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XtMalloc(3Xt)               X Version 11(Release 3)               XtMalloc(3Xt)


NAME
      XtMalloc, XtCalloc, XtRealloc, XtFree, XtNew, XtNewString - memory
      management functions

SYNTAX
      char *XtMalloc(size);
            Cardinal size;

      char *XtCalloc(num, size);
            Cardinal num;
            Cardinal size;

      char *XtRealloc(ptr, num);
            char *ptr;
            Cardinal num;

      void XtFree(ptr);
            char *ptr;

      type *XtNew(type);
            type;

      String XtNewString(string);
            String string;

ARGUMENTS
      num       Specifies the number of bytes or array elements.

      ptr       Specifies a pointer to the old storage or to the block of
                storage that is to be freed.

      size      Specifies the size of an array element (in bytes) or the number
                of bytes desired.

      string    Specifies a previously declared string.

      type      Specifies a previously declared data type.

DESCRIPTION
      The XtMalloc functions returns a pointer to a block of storage of at
      least the specified size bytes.  If there is insufficient memory to
      allocate the new block, XtMalloc calls XtErrorMsg.

      The XtCalloc function allocates space for the specified number of array
      elements of the specified size and initializes the space to zero.  If
      there is insufficient memory to allocate the new block, XtCalloc calls
      XtErrorMsg.

      The XtRealloc function changes the size of a block of storage (possibly
      moving it).  Then, it copies the old contents (or as much as will fit)
      into the new block and frees the old block.  If there is insufficient
      memory to allocate the new block, XtRealloc calls XtErrorMsg.  If ptr is


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XtMalloc(3Xt)               X Version 11(Release 3)               XtMalloc(3Xt)


      NULL, XtRealloc allocates the new storage without copying the old
      contents; that is, it simply calls XtMalloc.

      The XtFree function returns storage and allows it to be reused.  If ptr
      is NULL, XtFree returns immediately.

      XtNew returns a pointer to the allocated storage.  If there is
      insufficient memory to allocate the new block, XtNew calls XtErrorMsg.
      XtNew is a convenience macro that calls XtMalloc with the following
      arguments specified:

      ((type *) XtMalloc((unsigned) sizeof(type))

      XtNewString returns a pointer to the allocated storage.  If there is
      insufficient memory to allocate the new block, XtNewString calls
      XtErrorMsg.  XtNewString is a convenience macro that calls XtMalloc with
      the following arguments specified:

      (strcpy(XtMalloc((unsigned) strlen(str) + 1), str))

SEE ALSO
      X Toolkit Intrinsics - C Language Interface
      Xlib - C Language X Interface































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