Подтвердить наличие у клиента прав записи в ресурс
#include <sys/iofunc.h>int iofunc_write_verify( resmgr_context_t *ctp,io_write_t *msg,iofunc_ocb_t *ocb,int *nonblock );
NULL
, or a pointer to a location where the function can store a value that indicates whether or not the device is nonblocking: ≠0
— the client doesn't want to be blocked (i.e. O_NONBLOCK
was set). 0
— the client wants to be blocked. libc
The iofunc_write_verify() function checks that the client that sent the write message actually has write access to the resource, and, optionally (if nonblock isn't NULL
), sets nonblock to O_NONBLOCK
or 0
.
The write permission check is done against ocb->ioflag.
Note that the io_write_t message has an override flag called msg->i.xtype. This flag allows the client to override the default blocking behavior for the resource on a per-request basis. This override flag is checked, and returned in the optional nonblock.
In write callout for your resource manager, you'll need to indicate how many bytes were written. You can do this with the macro:
_IO_SET_WRITE_NBYTES( resmgr_context_t *ctp, int nbytes )
ЗОСРВ «Нейтрино»
io_write_t, iofunc_read_verify(), resmgr_context_t
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