61 lines
1.7 KiB
Plaintext
61 lines
1.7 KiB
Plaintext
.if n .pH ddi.rm/d3/gen/delay @(#)delay 43.10 of 11/27/92
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.\" Copyright 1992, 1991 UNIX System Laboratories, Inc.
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.TH delay D3
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.IX "\f4delay\fP(D3)"
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.SH "NAME"
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\f4delay\f1 \- delay process execution for a specified number of clock ticks
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.SH "SYNOPSIS"
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.nf
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.na
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.ft 4
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void delay(long \f2ticks\fP);
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.ft 1
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.ad
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.fi
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.SS Arguments
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.RS 0
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.IP "\f2ticks\f1" 10n
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The number of clock ticks to delay.
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.RE
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.SH "DESCRIPTION"
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\f4delay\f1 causes the caller to sleep for the amount of time specified
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by \f2ticks\f1, which is in units of clock ticks.
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The exact length of the delay is not guaranteed but it will not be less
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than \f2ticks -1\f1 clock ticks.
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.SS "Return Values"
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None
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.SH USAGE
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The length of a clock tick can vary across different implementations and
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therefore drivers should not include any hard-coded assumptions about
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the length of a tick.
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The \f4drv_usectohz\f1(D3) and \f4drv_hztousec\f1(D3) functions
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can be used, as necessary, to convert between clock ticks and microseconds
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(implementation independent units).
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.P
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The \f4delay\f1 function calls \f4itimeout\f1(D3)
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to schedule a wakeup after the specified amount of time has elapsed.
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\f4delay\f1 then goes to sleep until \f4itimeout\f1
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wakes up the sleeping process.
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.SS Level
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Base only.
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.SS "Synchronization Constraints"
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Can sleep.
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.P
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Driver-defined basic locks and read/write locks
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may not be held across calls to this function.
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.P
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Driver-defined sleep locks may be held across calls to this function,
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but this is discouraged because it can adversely affect performance
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by forcing any other processes contending for the lock to
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sleep for the duration of the delay.
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.SH REFERENCES
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.na
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\f4drv_hztousec\fP(D3),
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\f4drv_usectohz\fP(D3),
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\f4drv_usecwait\fP(D3),
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\f4itimeout\fP(D3),
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\f4sleep\fP(D3),
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\f4untimeout\fP(D3),
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\f4wakeup\fP(D3)
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.ad
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