io_sync()

int io_sync ( resmgr_context_t *ctp,
              io_sync_t *msg,
              RESMGR_OCB_T *ocb ) 

Classification: I/O

Default handler: iofunc_sync_default()

Helper functions: iofunc_sync_verify(), iofunc_sync()

Client functions: fsync(), fdatasync()

Messages: _IO_SYNC

Data structure:

struct _io_sync {
  uint16_t        type;
  uint16_t        combine_len;
  uint32_t        flag;
};

typedef union {
  struct _io_sync i;
} io_sync_t;

Description: This is the entry point for a flush command. The helper function iofunc_sync() is passed the flag member from the input message, and returns one of the following values, which indicate what actions your resource manager must take:

• 0—do nothing.
• O_SYNC—everything associated with the file (including the file contents, directory structures, inodes, etc.) must be present and recoverable from media.
• O_DSYNC—only the data portion of the file must be present and recoverable from media.

Note that this outcall will occur only if you've agreed to provide sync services by setting the mount structure flag.

Returns: Returns the status via the helper macro _RESMGR_STATUS().