AWRITE(9E)AWRITE(9E)NAMEawrite - asynchronous write to a device
intprefixawrite(dev_t dev, struct aio_req *aio_reqp,
Solaris DDI specific (Solaris DDI). This entry point is optional. Driv‐
ers that do not support an awrite() entry point should use nodev(9F)PARAMETERS
Pointer to the aio_req(9S) structure that describes where
the data is stored.
Pointer to the credential structure.
The driver's awrite() routine is called to perform an asynchronous
write. getminor(9F) can be used to access the minor number component
of the dev argument. awrite() may use the credential structure pointed
to by cred_p to check for superuser access by calling drv_priv(9F).
The awrite() routine may also examine the uio(9S) structure through
the aio_req structure pointer, aio_reqp. awrite() must call
aphysio(9F) with the aio_req pointer and a pointer to the driver's
No fields of the uio(9S) structure pointed to by aio_req, other than
uio_offset or uio_loffset, may be modified for non-seekable devices.
The awrite() routine should return 0 for success, or the appropriate
This function is called from user context only.
Example 1 Using the awrite() routine:
The following is an example of an awrite() routine:
xxawrite(dev_t dev, struct aio_req *aio, cred_t *cred_p)
struct xxstate *xsp;
instance = getminor(dev);
xsp = ddi_get_soft_state(statep, instance);
/*Verify soft state structure has been allocated */
if (xsp == NULL)
return (aphysio(xxstrategy, anocancel, dev, B_WRITE, \
SEE ALSOwrite(2), aiowrite(3C), aread(9E), read(9E), strategy(9E), write(9E),
anocancel(9F), aphysio(9F), ddi_get_soft_state(9F), drv_priv(9F), get‐
minor(9F), minphys(9F), nodev(9F), aio_req(9S), cb_ops(9S), uio(9S)
Writing Device Drivers
There is no way other than calling aphysio(9F) to accomplish an asyn‐
Mar 28, 1997 AWRITE(9E)