Kernel Functions for Drivers                         msgdsize(9F)



NAME
     msgdsize - return the number of bytes in a message

SYNOPSIS
     #include 



     sizet msgdsize(mblkt *mp);


INTERFACE LEVEL
     Architecture independent level 1 (DI/DKI).

PARAMETERS
     mp    Message to be evaluated.


DESCRIPTION
     The msgdsize() function counts the number of bytes in a data
     message.  Only  bytes  included  in  the data blocks of type
     MDATA are included in the count.

RETURN VALUES
     The number of data bytes  in  a  message,  expressed  as  an
     integer.

CONTEXT
     The msgdsize() function can be called from user,  interrupt,
     or kernel context.

EXAMPLES
     See bufcall(9F) for an example that uses msgdsize().

SEE ALSO
     bufcall(9F)


     Writing Device Drivers


     STREAMS Programming Guide













SunOS 5.11          Last change: 16 Jan 2006                    1