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XtMalloc(3Xt)                                       XtMalloc(3Xt)



NAME
     XtMalloc, XtCalloc, XtRealloc, XtFree, XtNew, XtNewString  -
     manage memory

SYNOPSIS
     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;

DESCRIPTION
     The XtMalloc function 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 initial-
     izes the space to 0.  If there is insufficient memory to al-
     locate 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 con-
     tents (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 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.

     The XtNew convenience macro returns a pointer to the allo-
     cated storage.  If there is insufficient memory to allocate
     the new block, XtNew calls XtErrorMsg.  XtNew calls XtMalloc
     with these arguments specified:




November, 1990                                                  1

XtMalloc(3Xt)                                       XtMalloc(3Xt)



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

     The XtNewString convenience macro returns a pointer to the
     allocated storage.  If there is insufficient memory to allo-
     cate the new block, XtNewString calls XtErrorMsg.
     XtNewString calls XtMalloc with these arguments specified:

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


   Arguments
     These functions and macros accept the following 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.

SEE ALSO
     X Toolkit Intrinsics - C Language Interface

     Xlib - C Language Interface



























2                                                  November, 1990