iofunc_stat_default()
Default handler for _IO_STAT messages
Synopsis:
#include <sys/iofunc.h> int iofunc_stat_default( resmgr_context_t *ctp, io_stat_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_stat_t structure that contains the message that the resource manager received; see below.
- 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_stat_default() function implements POSIX semantics for the client's stat() or fstat() call, which is received as an _IO_STAT message by the resource manager.
You can place this function directly into the io_funcs table passed to resmgr_attach(), at the stat position, or you can call iofunc_func_init() to initialize all of the functions to their default values.
The iofunc_stat_default() function calls:
- iofunc_time_update(), to ensure that the time entries in the ocb->attr structure are current and valid
- iofunc_stat() to construct a status entry based on the information in the ocb->attr structure.
io_stat_t structure
The io_stat_t structure holds the _IO_STAT message received by the resource manager:
struct _io_stat {
uint16_t type;
uint16_t combine_len;
uint32_t zero;
};
typedef union {
struct _io_stat i;
struct stat o;
} io_stat_t;
The I/O message structures are unions of an input message (coming to the resource manager) and an output or reply message (going back to the client).
The i member is a structure of type _io_stat that contains the following members:
- type
- _IO_STAT.
- combine_len
- If the message is a combine message, _IO_COMBINE_FLAG is set in this member.
The o member is a structure of type stat; for more information, see stat().
Returns:
-1, to indicate to the resource manager library that it should return one part from the ctp->iov structure (see resmgr_context_t) to the client, or an errno value if an error occurred.
Classification:
| Safety: | |
|---|---|
| Cancellation point | No |
| Interrupt handler | No |
| Signal handler | Yes |
| Thread | Yes |