msgdsize(9F)

NAME

     msgdsize - return the number of bytes in a message

SYNOPSIS

     #include <sys/stream.h>

     size_t msgdsize(mblk_t *mp);

INTERFACE LEVEL

     Architecture independent level 1 (DDI/DKI).

PARAMETERS

     mp    Message to be evaluated.

DESCRIPTION

     msgdsize() counts the number of bytes  in  a  data  message.
     Only  bytes  included in the data blocks of type  M_DATA are
     included in the count.

RETURN VALUES

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

CONTEXT

     msgdsize() can be called from user or interrupt context.

EXAMPLES

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

SEE ALSO

     bufcall(9F)

     Writing Device Drivers

      STREAMS Programming Guide