NAME    [Toc]    [Back]

       bufcall - STREAMS: Gets a buffer when allocb fails

SYNOPSIS    [Toc]    [Back]

       #include <sys/stream.h>

       int bufcall(
               int size,
               int pri,
               int (*function) (),
               long argument );

ARGUMENTS    [Toc]    [Back]

       Specifies  the  number  of bytes in the buffer.  Specifies
       the priority of the allocb allocation request  (no  longer
       used).   Specifies  a  kernel  or  driver  interface to be
       called when a  buffer  becomes  available.   Specifies  an
       argument  to  be  passed to the kernel or driver interface
       specified in the function argument.

DESCRIPTION    [Toc]    [Back]

       The bufcall interface serves as a timeout call of indeterminate
 length. When a buffer allocation request fails, you
       can use bufcall to schedule the interface  passed  to  the
       function argument to be called with the argument passed to
       argument when a buffer becomes  available.  The  interface
       passed  to  function can be a routine that calls allocb or
       it can be implemented to perform something else.

NOTES    [Toc]    [Back]

       Even when the bufcall interface calls the interface passed
       to  the  function argument, the allocb interface can still
       fail if another module or device driver allocated the memory
  before  the  interface  in  function was able to call
       allocb.

RETURN VALUES    [Toc]    [Back]

       Upon successful completion, the bufcall interface  returns
       a  bufcall  id that you can use in a call to the unbufcall
       interface to cancel the request. If the bufcall scheduling
       fails  (that is, a buffer is not available), the interface
       passed to function is never called and bufcall returns the
       value zero (0).

SEE ALSO    [Toc]    [Back]

       Kernel Routines: allocb(9r), esballoc(9r), testb(9r)

       Programmer's Guide: STREAMS



                                                      bufcall(9r)