iofunc_sync_verify()
Verify permissions to sync
Synopsis:
#include <sys/iofunc.h> int iofunc_sync_verify( resmgr_context_t *ctp, io_sync_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_sync_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_sync_verify() function verifies that the client has permission to synchronize.
io_sync_t structure
The io_sync_t structure holds the _IO_SYNC message received by the resource manager:
struct _io_sync { uint16_t type; uint16_t combine_len; uint32_t flag; }; typedef union { struct _io_sync i; } io_sync_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). In this case, there's only an input message, i.
The i member is a structure of type _io_sync that contains the following members:
- type
- _IO_SYNC.
- combine_len
- If the message is a combine message, _IO_COMBINE_FLAG is set in this member.
- flag
- One of:
- O_DSYNC
- O_RSYNC
- O_SYNC
For more information about these flags, see open() .
Returns:
- EINVAL
- The resource doesn't support syncing.
- EOK
- The client has read access to this resource.
Classification:
Safety: | |
---|---|
Cancellation point | No |
Interrupt handler | No |
Signal handler | Yes |
Thread | Yes |