Windows PowerShell command on Get-command untimeout
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Manual Pages for UNIX Operating System command usage for man untimeout

Kernel Functions for Drivers untimeout(9F)

NAME

untimeout - cancel previous timeout function call

SYNOPSIS

#include

#include

clock_t untimeout(timeout_id_t id);

INTERFACE LEVEL

Architecture independent level 1 (DDI/DKI).

PARAMETERS

id Opaque timeout ID from a previous timeout(9F) call.

DESCRIPTION

The untimeout() function cancels a pending timeout(9F)

request. untimeout() will not return until the pending call-

back is cancelled or has run. Because of this, locks acquired by the callback routine should not be held across

the call to untimeout() or a deadlock may result.

Since no mutex should be held across the call to

untimeout(), there is a race condition between the

occurrence of an expected event and the execution of the timeout handler. In particular, it should be noted that no

problems will result from calling untimeout() for a timeout

which is either running on another CPU, or has already com-

pleted. Drivers should be structured with the understanding that the arrival of both an interrupt and a timeout for that interrupt can occasionally occur, in either order.

RETURN VALUES

The untimeout() function returns -1 if the id is not found.

Otherwise, it returns an integer value greater than or equal to 0.

CONTEXT

The untimeout() function can be called from user, interrupt,

or kernel context.

EXAMPLES

In the following example, the device driver has issued an IO request and is waiting for the device to respond. If the device does not respond within 5 seconds, the device driver will print out an error message to the console.

SunOS 5.11 Last change: 16 Jan 2006 1

Kernel Functions for Drivers untimeout(9F)

static void

xxtimeout_handler(void *arg)

{ struct xxstate *xsp = (struct xxstate *)arg;

mutex_enter(&xsp->lock);

cv_signal(&xsp->cv);

xsp->flags |= TIMED_OUT;

mutex_exit(&xsp->lock);

xsp->timeout_id = 0;

}

static uint_t

xxintr(caddr_t arg)

{ struct xxstate *xsp = (struct xxstate *)arg; . . .

mutex_enter(&xsp->lock);

/* Service interrupt */

cv_signal(&xsp->cv);

mutex_exit(&xsp->lock);

if (xsp->timeout_id != 0) {

(void) untimeout(xsp->timeout_id);

xsp->timeout_id = 0;

}

return(DDI_INTR_CLAIMED);

} static void xxcheckcond(struct xxstate *xsp) { . . .

xsp->timeout_id = timeout(xxtimeout_handler,

xsp, (5 * drv_usectohz(1000000)));

mutex_enter(&xsp->lock);

while (/* Waiting for interrupt or timeout*/)

cv_wait(&xsp->cv, &xsp->lock);

if (xsp->flags & TIMED_OUT)

cmn_err(CE_WARN, "Device not responding");

. . .

mutex_exit(&xsp->lock);

. . . }

SEE ALSO

SunOS 5.11 Last change: 16 Jan 2006 2

Kernel Functions for Drivers untimeout(9F)

open(9E), cv_signal(9F), cv_wait_sig(9F), delay(9F),

timeout(9F) Writing Device Drivers

SunOS 5.11 Last change: 16 Jan 2006 3




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