Write a message to a client
#include <sys/resmgr.h>
int resmgr_msgwrite( resmgr_context_t *ctp,
const void *msg,
int size,
int offset );
- ctp
- A pointer to a
resmgr_context_t
structure that the resource-manager library uses to pass context information
between functions.
This function extracts the rcvid from this structure.
- msg
- A pointer to a buffer that contains the data you want to write.
- size
- The number of bytes that you want to write.
This function doesn't let you write past the end of the sender's buffer;
it returns the number of bytes actually written.
- offset
- An offset into the sender's buffer that indicates where you want
to start writing the data.
libc
Use the -l c option to
qcc
to link against this library.
This library is usually included automatically.
The function resmgr_msgwrite() is a cover for
MsgWrite()
and performs the exact same functionality.
The same values as MsgWrite();
the number of bytes written, or -1 if an
error occurs
(errno is set).
- EFAULT
- A fault occurred in the sender's address space when a server
tried to access the sender's return message buffer.
- ESRCH
- The thread indicated by ctp -> rcvid
does not exist or has had its connection detached.
- ESRVRFAULT
- A fault occurred when the kernel tried to access the buffers
provided.
QNX Neutrino
Safety: | |
Cancellation point |
No |
Interrupt handler |
No |
Signal handler |
Yes |
Thread |
Yes |
MsgWrite(),
resmgr_context_t,
resmgr_msgread(),
resmgr_msgreadv(),
resmgr_msgwritev()
“Layers in a resource manager”
in the Bones of a Resource Manager chapter of Writing a Resource Manager
Resource Managers
chapter of Getting Started with QNX Neutrino