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ZCLOCK(3) CZMQ Manual ZCLOCK(3)

NAME

zclock - Class for millisecond clocks and delays

SYNOPSIS

//  This is a stable class, and may not change except for emergencies. It
//  is provided in stable builds.
//  Sleep for a number of milliseconds
CZMQ_EXPORT void

zclock_sleep (int msecs); // Return current system clock as milliseconds. Note that this clock can // jump backwards (if the system clock is changed) so is unsafe to use for // timers and time offsets. Use zclock_mono for that instead. CZMQ_EXPORT int64_t
zclock_time (void); // Return current monotonic clock in milliseconds. Use this when you compute // time offsets. The monotonic clock is not affected by system changes and // so will never be reset backwards, unlike a system clock. CZMQ_EXPORT int64_t
zclock_mono (void); // Return current monotonic clock in microseconds. Use this when you compute // time offsets. The monotonic clock is not affected by system changes and // so will never be reset backwards, unlike a system clock. CZMQ_EXPORT int64_t
zclock_usecs (void); // Return formatted date/time as fresh string. Free using zstr_free(). // Caller owns return value and must destroy it when done. CZMQ_EXPORT char *
zclock_timestr (void); // Self test of this class. CZMQ_EXPORT void
zclock_test (bool verbose); Please add '@interface' section in './../src/zclock.c'.

DESCRIPTION

The zclock class provides essential sleep and system time functions, used to slow down threads for testing, and calculate timers for polling. Wraps the non-portable system calls in a simple portable API.

The Win32 Sleep() call defaults to 16ms resolution unless the system timer resolution is increased with a call to timeBeginPeriod() permitting 1ms granularity.

EXAMPLE

From zclock_test method.

int64_t start = zclock_time ();
zclock_sleep (10);
assert ((zclock_time () - start) >= 10);
start = zclock_mono ();
int64_t usecs = zclock_usecs ();
zclock_sleep (10);
assert ((zclock_mono () - start) >= 10);
assert ((zclock_usecs () - usecs) >= 10000);
char *timestr = zclock_timestr ();
if (verbose)

puts (timestr); freen (timestr); #if defined (__WINDOWS__) zsys_shutdown(); #endif

AUTHORS

The czmq manual was written by the authors in the AUTHORS file.

RESOURCES

Main web site:

Report bugs to the email <zeromq-dev@lists.zeromq.org[1]>

COPYRIGHT

Copyright (c) the Contributors as noted in the AUTHORS file. This file is part of CZMQ, the high-level C binding for 0MQ: http://czmq.zeromq.org. This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of the MPL was not distributed with this file, You can obtain one at http://mozilla.org/MPL/2.0/. LICENSE included with the czmq distribution.

NOTES

1.
zeromq-dev@lists.zeromq.org
mailto:zeromq-dev@lists.zeromq.org
01/17/2021 CZMQ 4.2.1