MsgError(), MsgError_r()

Unblock a client and set its errno

Synopsis:

#include <sys/neutrino.h>

int MsgError( int rcvid,
              int error );

int MsgError_r( int rcvid,
                int error );

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

The MsgError() and MsgError_r() kernel calls unblock the client's MsgSend*() call and set the client's errno to error. No data is transferred.

If error is EOK, the MsgSend*() call returns EOK; if error is any other value, the MsgSend*() call returns -1.

These functions are identical except in the way they indicate errors. See the Returns section for details.

An error number of ERESTART causes the sender to immediately call MsgSend*() again. Since send and reply buffers passed to MsgSend() may overlap, you shouldn't use ERESTART after a call to MsgWrite() .

Blocking states

None. In the network case, lower priority threads may run.

The only difference between these functions is the way they indicate errors:

MsgError(): If an error occurs, the function returns -1 and and sets errno . Any other value returned indicates success.
MsgError_r(): Returns EOK on success. This function does NOT set errno. If an error occurs, the function returns one of the values listed in the Errors section.