iofunc_write_default()
Default handler for _IO_WRITE messages
Synopsis:
#include <sys/iofunc.h>
int iofunc_write_default( resmgr_context_t* ctp,
io_write_t* msg,
iofunc_ocb_t* ocb );
Arguments:
- ctp
- A pointer to a resmgr_context_t structure that the resource-manager library uses to pass context information between functions.
- msg
- A pointer to the io_write_t structure that contains the message that the
resource manager received. For information on this structure, see the
Handling the _IO_WRITE message
topic in the Writing a Resource Manager guide. - ocb
- A pointer to the iofunc_ocb_t structure for the Open Control Block that was created when the client opened the resource.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The iofunc_write_default() function implements POSIX semantics for the client's write() call, which is received as an _IO_WRITE message by the resource manager. It doesn't actually write the given data anywhere.
You can place this function directly into the resmgr_io_funcs_t table passed as the io_funcs argument to resmgr_attach(), at the write position, or you can call iofunc_func_init() to initialize all of the functions to their default values.
The iofunc_write_default() function calls iofunc_write_verify() to verify if this write operation should be permitted. If so, iofunc_write_default() indicates that it wrote the requested number of bytes.
Returns:
- EOK
- This write operation was permitted.
- EBADF
- The client doesn't have write access to this resource.
- EINVAL
- An unknown xtype was given.
Classification:
Safety: | |
---|---|
Cancellation point | No |
Signal handler | Yes |
Thread | Yes |