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1013:"Rationale for American National Standard for Information Systems - Programming Language - C - Date and Time"
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and related types were originally proposed by Markus Kuhn to provide a variety of time bases, but only
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system command includes various formatting options. In 1989, the ANSI C standard is released including
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341:). The value of the epoch is operating system dependent; 1900 and 1970 are often used. See RFC 868.
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was accepted. The functionalities were, however, added to C++ in 2020 in std::chrono.
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acquisition, conversion between date formats, and formatted output to strings.
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implementing date and time manipulation operations. They provide support for
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The following C source code prints the current time to the
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value, number of seconds, (which is usually time since an
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object to custom wide string textual representation
549:time type: year, month, day, hour, minute, second
266:The C date and time operations are defined in the
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391:object to a textual representation (deprecated)
561:arithmetic time type (typically time since the
489:value to calendar time expressed as local time
309:computes the difference in seconds between two
1078:
1030:open-std.org - Committee Draft -- May 6, 2005
435:converts a string with time information to a
370:returns a calendar time based on a time base
199:
520:number of processor clock ticks per second
1092:
1085:
1071:
842:"Failure to convert the current time.
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192:
749:"Failure to obtain the current time.
921:Current time is Thu Sep 15 21:18:23 2016
423:object to custom textual representation
261:
1041:
1576:
1066:
977:"PWB1 date system command - man page"
470:value to calendar time expressed as
18:
776:/* Convert to local time format. */
258:and other date and time functions.
13:
589:time with seconds and nanoseconds
407:value to a textual representation
14:
1600:
1058:
508:
45:and remove advice or instruction.
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222:are a group of functions in the
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959:ISO/IEC 9899:1999 specification
360:
1035:
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1005:
987:
969:
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887:"Current time is %s"
1:
943:
501:converts calendar time to a
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357:associated with the process
7:
995:"date.c sourcecode of PWB1"
926:
580:
441:
426:
410:
295:
10:
1605:
1469:Compatibility of C and C++
1044:"Modernized API for ISO C"
677:/* Obtain current time. */
606:
577:process running time type
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472:Coordinated Universal Time
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242:The format string used in
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220:C date and time functions
918:
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250:, released in 1977. Its
246:traces back to at least
88:Character classification
316:
1474:Comparison with Pascal
1094:C programming language
613:standard output stream
228:C programming language
533:
262:Overview of functions
141:Miscellaneous headers
16:Library of C programs
355:processor tick count
325:returns the current
43:rewrite this article
965:. p. 351, § 7.32.2.
1584:C standard library
1017:www.lysator.liu.se
530:time base for UTC
327:time of the system
133:Alternative tokens
68:C standard library
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938:Year 2038 problem
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118:Memory allocation
103:File input/output
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36:a manual or guide
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1460:Comparison with
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1247:Implementations
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916:The output is:
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123:Process control
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1543:Dennis Ritchie
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1059:External links
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75:General topics
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1076:
1074:
1069:
1068:
1065:
1049:
1045:
1042:Markus Kuhn.
1038:
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1018:
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978:
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917:
893:c_time_string
806:c_time_string
779:c_time_string
671:c_time_string
616:
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299:manipulation
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32:This article
30:
21:
20:
1560:
1416:Code::Blocks
1388:Watcom C/C++
1227:
1176:Preprocessor
1156:Header files
1048:cl.cam.ac.uk
1047:
1037:
1025:
1016:
1007:
999:www.tuhs.org
998:
989:
981:www.tuhs.org
980:
971:
958:
952:
915:
905:EXIT_SUCCESS
860:EXIT_FAILURE
794:current_time
767:EXIT_FAILURE
704:current_time
680:current_time
659:current_time
610:
594:
545:broken-down
377:conversions
364:timespec_get
292:Description
265:
248:PWB/UNIX 1.0
241:
219:
217:
113:Localization
107:
61:
51:October 2014
48:
41:Please help
33:
1507:Objective-C
1288:Windows CRT
485:converts a
466:converts a
450:converts a
419:converts a
403:converts a
387:converts a
289:Identifier
271:header file
98:Mathematics
1578:Categories
1483:Descendant
1355:Norcroft C
1181:Data types
1130:Embedded C
944:References
563:Unix epoch
510:Constants
353:returns a
339:Unix epoch
277:header in
83:Data types
1485:languages
1317:Compilers
1259:libhybris
1161:Operators
1151:Functions
933:Unix time
540:struct tm
480:localtime
452:struct tm
437:struct tm
421:struct tm
389:struct tm
108:Date/time
1562:Category
1536:Designer
1451:NetBeans
1441:KDevelop
1421:CodeLite
1266:dietlibc
1233:Variadic
1208:File I/O
1144:Features
1032:page 355
927:See also
632:#include
626:#include
620:#include
601:TIME_UTC
597:timespec
584:timespec
547:calendar
526:TIME_UTC
445:wcsftime
430:strptime
414:strftime
304:difftime
256:strftime
244:strftime
178:stdarg.h
169:setjmp.h
151:assert.h
1426:Eclipse
1379:Express
1135:MISRA C
830:fprintf
737:fprintf
607:Example
572:clock_t
505:value.
382:asctime
313:values
238:History
226:of the
160:errno.h
128:Signals
93:Strings
1406:Anjuta
1303:uClibc
1298:Newlib
1276:EGLIBC
1254:Bionic
1223:String
1171:Syntax
1166:String
1105:ANSI C
881:printf
848:"
836:stderr
755:"
743:stderr
713:time_t
656:time_t
556:time_t
535:Types
503:time_t
496:mktime
487:time_t
468:time_t
461:gmtime
405:time_t
375:Format
367:(C11)
331:time_t
311:time_t
268:time.h
70:(libc)
1517:Limbo
1431:Geany
1411:CLion
1335:Clang
1283:klibc
1271:glibc
1238:POSIX
963:(PDF)
791:&
785:ctime
398:ctime
348:clock
335:epoch
329:as a
275:ctime
1589:Time
1527:Vala
1512:Alef
1398:IDEs
1365:SDCC
1293:musl
1228:Time
1213:Math
1203:Char
899:exit
875:void
854:exit
824:void
812:NULL
761:exit
731:void
692:NULL
686:time
665:char
647:void
641:main
595:The
320:time
297:Time
252:date
232:time
218:The
180:>
176:<
171:>
167:<
162:>
158:<
153:>
149:<
1492:C++
1383:C++
1370:TCC
1360:PCC
1350:LCC
1345:ICC
1340:GCC
1325:ACK
1125:C23
1120:C17
1115:C11
1110:C99
638:int
281:).
279:C++
1580::
1522:Go
1497:C#
1381:,
1377:,
1046:.
1015:.
997:.
979:.
908:);
896:);
863:);
851:);
845:\n
809:==
800:if
797:);
770:);
758:);
752:\n
722:))
719:-1
710:((
707:==
698:if
695:);
615:.
565:)
1502:D
1086:e
1079:t
1072:v
1050:.
1019:.
1001:.
983:.
911:}
902:(
890:,
884:(
878:)
872:(
866:}
857:(
839:,
833:(
827:)
821:(
818:{
815:)
803:(
788:(
782:=
773:}
764:(
746:,
740:(
734:)
728:(
725:{
716:)
701:(
689:(
683:=
674:;
668:*
662:;
653:{
650:)
644:(
273:(
207:e
200:t
193:v
53:)
49:(
38:.
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