1 '\" te
2 .\" Copyright (c) 2014 Gary Mills
3 .\" Copyright (c) 2008, Sun Microsystems, Inc. All Rights Reserved.
4 .\" Copyright 1989 AT&T
5 .\" Portions Copyright (c) 1992, X/Open Company Limited. All Rights Reserved.
6 .\" Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
7 .\" http://www.opengroup.org/bookstore/.
8 .\" The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html.
9 .\" This notice shall appear on any product containing this material.
10 .\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
11 .\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
12 .\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
13 .TH STRFTIME 3C "Jan 3, 2014"
14 .SH NAME
15 strftime, cftime, ascftime \- convert date and time to string
16 .SH SYNOPSIS
17 .LP
18 .nf
19 #include <time.h>
20
21 \fBsize_t\fR \fBstrftime\fR(\fBchar *restrict\fR \fIs\fR, \fBsize_t\fR \fImaxsize\fR,
22 \fBconst char *restrict\fR \fIformat\fR,
23 \fBconst struct tm *restrict\fR \fItimeptr\fR);
24 .fi
25
26 .LP
27 .nf
28 \fBint\fR \fBcftime\fR(\fBchar *\fR\fIs\fR, \fBchar *\fR\fIformat\fR, \fBconst time_t *\fR\fIclock\fR);
29 .fi
30
31 .LP
32 .nf
33 \fBint\fR \fBascftime\fR(\fBchar *\fR\fIs\fR, \fBconst char *\fR\fIformat\fR,
34 \fBconst struct tm *\fR\fItimeptr\fR);
35 .fi
36
37 .SH DESCRIPTION
38 .sp
39 .LP
40 The \fBstrftime()\fR, \fBascftime()\fR, and \fBcftime()\fR functions place
41 bytes into the array pointed to by \fIs\fR as controlled by the string pointed
42 to by \fIformat\fR. The \fIformat\fR string consists of zero or more conversion
43 specifications and ordinary characters. A conversion specification consists of
44 a '\fB%\fR' (percent) character and one or two terminating conversion
45 characters that determine the conversion specification's behavior. All
46 ordinary characters (including the terminating null byte) are copied unchanged
47 into the array pointed to by \fIs\fR. If copying takes place between objects
48 that overlap, the behavior is undefined. For \fBstrftime()\fR, no more than
49 \fImaxsize\fR bytes are placed into the array.
50 .sp
51 .LP
52 If \fIformat\fR is \fB(char *)0\fR, then the locale's default format is used.
53 For \fBstrftime()\fR the default format is the same as \fB%c\fR; for
54 \fBcftime()\fR and \fBascftime()\fR the default format is the same as \fB%+\fR.
55 \fBcftime()\fR and \fBascftime()\fR first try to use the value of the
56 environment variable \fBCFTIME\fR, and if that is undefined or empty, the
57 default format is used.
58 .sp
59 .LP
60 Each conversion specification is replaced by appropriate characters as
61 described in the following list. The appropriate characters are determined by
62 the \fBLC_TIME\fR category of the program's locale and by the values contained
63 in the structure pointed to by \fItimeptr\fR for \fBstrftime()\fR and
64 \fBascftime()\fR, and by the time represented by \fIclock\fR for
65 \fBcftime()\fR.
66 .sp
67 .ne 2
68 .na
69 \fB\fB%%\fR\fR
70 .ad
71 .RS 6n
72 Same as \fB%\fR.
73 .RE
74
75 .sp
76 .ne 2
77 .na
78 \fB\fB%a\fR\fR
448 .RE
449
450 .sp
451 .ne 2
452 .na
453 \fB\fB%Z\fR\fR
454 .ad
455 .RS 6n
456 Time zone name or abbreviation, or no bytes if no time zone information exists.
457 .RE
458
459 .sp
460 .ne 2
461 .na
462 \fB\fB%+\fR\fR
463 .ad
464 .RS 6n
465 Locale's date and time representation as produced by \fBdate\fR(1).
466 .RE
467
468 .sp
469 .LP
470 If a conversion specification does not correspond to any of the above or to any
471 of the modified conversion specifications listed below, the behavior is
472 undefined and \fB0\fR is returned.
473 .sp
474 .LP
475 The difference between \fB%U\fR and \fB%W\fR (and also between modified
476 conversion specifications \fB%OU\fR and \fB%OW\fR) lies in which day is counted
477 as the first of the week. Week number 1 is the first week in January starting
478 with a Sunday for \fB%U\fR or a Monday for \fB%W\fR. Week number 0 contains
479 those days before the first Sunday or Monday in January for \fB%U\fR and
480 \fB%W\fR, respectively.
481 .SS "Modified Conversion Specifications"
482 .sp
483 .LP
484 Some conversion specifications can be modified by the \fBE\fR and \fBO\fR
485 modifiers to indicate that an alternate format or specification should be used
486 rather than the one normally used by the unmodified conversion specification.
487 If the alternate format or specification does not exist in the current locale,
488 the behavior will be as if the unmodified specification were used.
489 .sp
490 .ne 2
491 .na
492 \fB\fB%Ec\fR\fR
493 .ad
494 .RS 7n
495 Locale's alternate appropriate date and time representation.
496 .RE
497
498 .sp
499 .ne 2
500 .na
501 \fB\fB%EC\fR\fR
502 .ad
664 .ne 2
665 .na
666 \fB\fB%OW\fR\fR
667 .ad
668 .RS 7n
669 Week number of the year (Monday as the first day of the week) using the
670 locale's alternate numeric symbols.
671 .RE
672
673 .sp
674 .ne 2
675 .na
676 \fB\fB%Oy\fR\fR
677 .ad
678 .RS 7n
679 Year (offset from \fB%C\fR) in the locale's alternate representation and using
680 the locale's alternate numeric symbols.
681 .RE
682
683 .SS "Selecting the Output Language"
684 .sp
685 .LP
686 By default, the output of \fBstrftime()\fR, \fBcftime()\fR, and
687 \fBascftime()\fR appear in U.S. English. The user can request that the output
688 of \fBstrftime()\fR, \fBcftime()\fR, or \fBascftime()\fR be in a specific
689 language by setting the \fBLC_TIME\fR category using \fBsetlocale()\fR.
690 .SS "Time Zone"
691 .sp
692 .LP
693 Local time zone information is used as though \fBtzset\fR(3C) were called.
694 .SH RETURN VALUES
695 .sp
696 .LP
697 The \fBstrftime()\fR, \fBcftime()\fR, and \fBascftime()\fR functions return the
698 number of characters placed into the array pointed to by \fIs\fR, not including
699 the terminating null character. If the total number of resulting characters
700 including the terminating null character is more than \fImaxsize\fR,
701 \fBstrftime()\fR returns \fB0\fR and the contents of the array are
702 indeterminate.
703 .SH EXAMPLES
704 .LP
705 \fBExample 1 \fRAn example of the \fBstrftime()\fR function.
706 .sp
707 .LP
708 The following example illustrates the use of \fBstrftime()\fR for the
709 \fBPOSIX\fR locale. It shows what the string in \fIstr\fR would look like if
710 the structure pointed to by \fItmptr\fR contains the values corresponding to
711 Thursday, August 28, 1986 at 12:44:36.
712
713 .sp
714 .in +2
715 .nf
716 \fBstrftime (str, strsize, "%A %b %d %j", tmptr)\fR
717 .fi
718 .in -2
719
720 .sp
721 .LP
722 This results in \fIstr\fR containing "Thursday Aug 28 240".
723
724 .SH ATTRIBUTES
725 .sp
726 .LP
727 See \fBattributes\fR(5) for descriptions of the following attributes:
728 .sp
729
730 .sp
731 .TS
732 box;
733 c | c
734 l | l .
735 ATTRIBUTE TYPE ATTRIBUTE VALUE
736 _
737 CSI Enabled
738 _
739 Interface Stability Committed
740 _
741 MT-Level MT-Safe
742 _
743 Standard See below.
744 .TE
745
746 .sp
747 .LP
748 For \fBstrftime()\fR, see \fBstandards\fR(5).
749 .SH SEE ALSO
750 .sp
751 .LP
752 \fBdate\fR(1), \fBctime\fR(3C), \fBmktime\fR(3C), \fBsetlocale\fR(3C),
753 \fBstrptime\fR(3C), \fBtzset\fR(3C), \fBTIMEZONE\fR(4), \fBzoneinfo\fR(4),
754 \fBattributes\fR(5), \fBenviron\fR(5), \fBstandards\fR(5)
755 .SH NOTES
756 .sp
757 .LP
758 The conversion specification for \fB%V\fR was changed in the Solaris 7 release.
759 This change was based on the public review draft of the ISO C9x standard at
760 that time. Previously, the specification stated that if the week containing 1
761 January had fewer than four days in the new year, it became week 53 of the
762 previous year. The ISO C9x standard committee subsequently recognized that that
763 specification had been incorrect.
764 .sp
765 .LP
766 The conversion specifications for \fB%g\fR, \fB%G\fR, \fB%Eg\fR, \fB%EG\fR, and
767 \fB%Og\fR were added in the Solaris 7 release. This change was based on the
768 public review draft of the ISO C9x standard at that time. These specifications
769 are evolving. If the ISO C9x standard is finalized with a different
770 conclusion, these specifications will change to conform to the ISO C9x standard
771 decision.
772 .sp
773 .LP
774 The conversion specification for \fB%u\fR was changed in the Solaris 8 release.
775 This change was based on the XPG4 specification.
776 .sp
777 .LP
778 If using the \fB%Z\fR specifier and \fBzoneinfo\fR timezones and if the input
779 date is outside the range 20:45:52 UTC, December 13, 1901 to 03:14:07 UTC,
780 January 19, 2038, the timezone name may not be correct.
781 .sp
782 .LP
783 The conversion specification for \fB%+\fR was added in illumos.
784 It is not part of any standard, although it is available on a number
785 of other platforms.
786 Its use is discouraged for conforming applications.
|
1 '\" te
2 .\" Copyright 2014 Garrett D'Amore <garrett@damore.org>
3 .\" Copyright (c) 2014 Gary Mills
4 .\" Copyright (c) 2008, Sun Microsystems, Inc. All Rights Reserved.
5 .\" Copyright 1989 AT&T
6 .\" Portions Copyright (c) 1992, X/Open Company Limited. All Rights Reserved.
7 .\" Sun Microsystems, Inc. gratefully acknowledges The Open Group for permission to reproduce portions of its copyrighted documentation. Original documentation from The Open Group can be obtained online at
8 .\" http://www.opengroup.org/bookstore/.
9 .\" The Institute of Electrical and Electronics Engineers and The Open Group, have given us permission to reprint portions of their documentation. In the following statement, the phrase "this text" refers to portions of the system documentation. Portions of this text are reprinted and reproduced in electronic form in the Sun OS Reference Manual, from IEEE Std 1003.1, 2004 Edition, Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2004 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between these versions and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html.
10 .\" This notice shall appear on any product containing this material.
11 .\" The contents of this file are subject to the terms of the Common Development and Distribution License (the "License"). You may not use this file except in compliance with the License.
12 .\" You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE or http://www.opensolaris.org/os/licensing. See the License for the specific language governing permissions and limitations under the License.
13 .\" When distributing Covered Code, include this CDDL HEADER in each file and include the License file at usr/src/OPENSOLARIS.LICENSE. If applicable, add the following below this CDDL HEADER, with the fields enclosed by brackets "[]" replaced with your own identifying information: Portions Copyright [yyyy] [name of copyright owner]
14 .TH STRFTIME 3C "Jun 24, 2014"
15 .SH NAME
16 strftime, strftime_l cftime, ascftime \- convert date and time to string
17 .SH SYNOPSIS
18 .LP
19 .nf
20 #include <time.h>
21
22 \fBsize_t\fR \fBstrftime\fR(\fBchar *restrict\fR \fIs\fR, \fBsize_t\fR \fImaxsize\fR,
23 \fBconst char *restrict\fR \fIformat\fR,
24 \fBconst struct tm *restrict\fR \fItimeptr\fR);
25 .fi
26 .LP
27 .nf
28 \fBsize_t\fR \fBstrftime_l\fR(\fBchar *restrict\fR \fIs\fR, \fBsize_t\fR \fImaxsize\fR,
29 \fBconst char *restrict\fR \fIformat\fR,
30 \fBconst struct tm *restrict\fR \fItimeptr\fR, \fBlocale_t\fR \fIloc\fR);
31 .fi
32 .LP
33 .nf
34 \fBint\fR \fBcftime\fR(\fBchar *\fR\fIs\fR, \fBchar *\fR\fIformat\fR, \fBconst time_t *\fR\fIclock\fR);
35 .fi
36 .LP
37 .nf
38 \fBint\fR \fBascftime\fR(\fBchar *\fR\fIs\fR, \fBconst char *\fR\fIformat\fR,
39 \fBconst struct tm *\fR\fItimeptr\fR);
40 .fi
41
42 .SH DESCRIPTION
43 .sp
44 .LP
45 The \fBstrftime()\fR, \fBstrftime_l()\fR, \fBascftime()\fR, and \fBcftime()\fR
46 functions place
47 bytes into the array pointed to by \fIs\fR as controlled by the string pointed
48 to by \fIformat\fR. The \fIformat\fR string consists of zero or more conversion
49 specifications and ordinary characters. A conversion specification consists of
50 a '\fB%\fR' (percent) character and one or two terminating conversion
51 characters that determine the conversion specification's behavior. All
52 ordinary characters (including the terminating null byte) are copied unchanged
53 into the array pointed to by \fIs\fR. If copying takes place between objects
54 that overlap, the behavior is undefined. For \fBstrftime()\fR, no more than
55 \fImaxsize\fR bytes are placed into the array. The \fBstrftime_l()\fR function
56 behaves identically to \fBstrftime()\fR function, but instead of operating in
57 the current locale, it operates in the locale specified by \fIloc\fR.
58 .LP
59 If \fIformat\fR is \fB(char *)0\fR, then the locale's default format is used.
60 For \fBstrftime()\fR the default format is the same as \fB%c\fR; for
61 \fBcftime()\fR and \fBascftime()\fR the default format is the same as \fB%+\fR.
62 \fBcftime()\fR and \fBascftime()\fR first try to use the value of the
63 environment variable \fBCFTIME\fR, and if that is undefined or empty, the
64 default format is used.
65 .LP
66 Each conversion specification is replaced by appropriate characters as
67 described in the following list. The appropriate characters are determined by
68 the \fBLC_TIME\fR category of the program's locale and by the values contained
69 in the structure pointed to by \fItimeptr\fR for \fBstrftime()\fR and
70 \fBascftime()\fR, and by the time represented by \fIclock\fR for
71 \fBcftime()\fR.
72 .sp
73 .ne 2
74 .na
75 \fB\fB%%\fR\fR
76 .ad
77 .RS 6n
78 Same as \fB%\fR.
79 .RE
80
81 .sp
82 .ne 2
83 .na
84 \fB\fB%a\fR\fR
454 .RE
455
456 .sp
457 .ne 2
458 .na
459 \fB\fB%Z\fR\fR
460 .ad
461 .RS 6n
462 Time zone name or abbreviation, or no bytes if no time zone information exists.
463 .RE
464
465 .sp
466 .ne 2
467 .na
468 \fB\fB%+\fR\fR
469 .ad
470 .RS 6n
471 Locale's date and time representation as produced by \fBdate\fR(1).
472 .RE
473
474 .LP
475 If a conversion specification does not correspond to any of the above or to any
476 of the modified conversion specifications listed below, the behavior is
477 undefined and \fB0\fR is returned.
478 .LP
479 The difference between \fB%U\fR and \fB%W\fR (and also between modified
480 conversion specifications \fB%OU\fR and \fB%OW\fR) lies in which day is counted
481 as the first of the week. Week number 1 is the first week in January starting
482 with a Sunday for \fB%U\fR or a Monday for \fB%W\fR. Week number 0 contains
483 those days before the first Sunday or Monday in January for \fB%U\fR and
484 \fB%W\fR, respectively.
485 .SS "Modified Conversion Specifications"
486 .LP
487 Some conversion specifications can be modified by the \fBE\fR and \fBO\fR
488 modifiers to indicate that an alternate format or specification should be used
489 rather than the one normally used by the unmodified conversion specification.
490 If the alternate format or specification does not exist in the current locale,
491 the behavior will be as if the unmodified specification were used.
492 .sp
493 .ne 2
494 .na
495 \fB\fB%Ec\fR\fR
496 .ad
497 .RS 7n
498 Locale's alternate appropriate date and time representation.
499 .RE
500
501 .sp
502 .ne 2
503 .na
504 \fB\fB%EC\fR\fR
505 .ad
667 .ne 2
668 .na
669 \fB\fB%OW\fR\fR
670 .ad
671 .RS 7n
672 Week number of the year (Monday as the first day of the week) using the
673 locale's alternate numeric symbols.
674 .RE
675
676 .sp
677 .ne 2
678 .na
679 \fB\fB%Oy\fR\fR
680 .ad
681 .RS 7n
682 Year (offset from \fB%C\fR) in the locale's alternate representation and using
683 the locale's alternate numeric symbols.
684 .RE
685
686 .SS "Selecting the Output Language"
687 .LP
688 These routines produce output that is formatted according to the \fBLC_TIME\fR
689 locale category. They use either the current locale, or in the case of
690 \fBstrftime_l()\fR, the locale supplied by \fIloc\fR.
691 .SS "Time Zone"
692 .LP
693 Local time zone information is used as though \fBtzset\fR(3C) were called.
694 .SH RETURN VALUES
695 .LP
696 These functions return the
697 number of characters placed into the array pointed to by \fIs\fR, not including
698 the terminating null character. If the total number of resulting characters
699 including the terminating null character is more than \fImaxsize\fR,
700 \fBstrftime()\fR returns \fB0\fR and the contents of the array are
701 indeterminate.
702 .SH EXAMPLES
703 .LP
704 \fBExample 1 \fRAn example of the \fBstrftime()\fR function.
705 .LP
706 The following example illustrates the use of \fBstrftime()\fR for the
707 \fBPOSIX\fR locale. It shows what the string in \fIstr\fR would look like if
708 the structure pointed to by \fItmptr\fR contains the values corresponding to
709 Thursday, August 28, 1986 at 12:44:36.
710 .nf
711 .IP
712 \fBstrftime\fR(\fIstr\fR, \fIstrsize\fR, "%A %b %d %j", \fItmptr\fR);
713 .fi
714 .LP
715 This results in \fIstr\fR containing "Thursday Aug 28 240".
716 .SH ATTRIBUTES
717 .LP
718 See \fBattributes\fR(5) for descriptions of the following attributes:
719 .TS
720 box;
721 c | c
722 l | l .
723 ATTRIBUTE TYPE ATTRIBUTE VALUE
724 _
725 CSI Enabled
726 _
727 Interface Stability See below.
728 _
729 MT-Level MT-Safe
730 _
731 Standard See below.
732 .TE
733
734 .LP
735 The \fBstrftime()\fR and \fBstrftime_l()\fR functions are Standard.
736 \fBcftime()\fR and \fBascftime()\fR functions are Committed.
737 .LP
738 For \fBstrftime()\fR and \fBstrftime_l()\fR, see \fBstandards\fR(5).
739 .SH SEE ALSO
740 .LP
741 \fBdate\fR(1), \fBctime\fR(3C), \fBmktime\fR(3C),
742 \fBnewlocale\fR(3C), \fBsetlocale\fR(3C), \fBstrptime\fR(3C), \fBtzset\fR(3C),
743 \fBuselocale\fR(3C), \fBTIMEZONE\fR(4), \fBzoneinfo\fR(4),
744 \fBattributes\fR(5), \fBenviron\fR(5), \fBstandards\fR(5)
745 .SH NOTES
746 .LP
747 The conversion specification for \fB%V\fR was changed in the Solaris 7 release.
748 This change was based on the public review draft of the ISO C9x standard at
749 that time. Previously, the specification stated that if the week containing 1
750 January had fewer than four days in the new year, it became week 53 of the
751 previous year. The ISO C9x standard committee subsequently recognized that that
752 specification had been incorrect.
753 .LP
754 The conversion specifications for \fB%g\fR, \fB%G\fR, \fB%Eg\fR, \fB%EG\fR, and
755 \fB%Og\fR were added in the Solaris 7 release. This change was based on the
756 public review draft of the ISO C9x standard at that time. The \fB%g\fR and
757 \fB%G\fR specifications were adopted in the formal standard. The other two
758 were not, and should not be used in portable applications.
759 .LP
760 The conversion specification for \fB%u\fR was changed in the Solaris 8 release.
761 This change was based on the XPG4 specification.
762 .LP
763 If using the \fB%Z\fR specifier and \fBzoneinfo\fR timezones and if the input
764 date is outside the range 20:45:52 UTC, December 13, 1901 to 03:14:07 UTC,
765 January 19, 2038, the timezone name may not be correct.
766 .LP
767 The conversion specification for \fB%+\fR was added in illumos.
768 It is not part of any standard, although it is available on a number
769 of other platforms.
770 Its use is discouraged for conforming applications.
|