newstrftime.3 6.6 KB

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  1. .\" Based on the UCB file whose copyright information appears below.
  2. .\" Copyright (c) 1989, 1991 The Regents of the University of California.
  3. .\" All rights reserved.
  4. .\"
  5. .\" This code is derived from software contributed to Berkeley by
  6. .\" the American National Standards Committee X3, on Information
  7. .\" Processing Systems.
  8. .\"
  9. .\" Redistribution and use in source and binary forms, with or without
  10. .\" modification, are permitted provided that the following conditions
  11. .\" are met:
  12. .\" 1. Redistributions of source code must retain the above copyright
  13. .\" notice, this list of conditions and the following disclaimer.
  14. .\" 2. Redistributions in binary form must reproduce the above copyright
  15. .\" notice, this list of conditions and the following disclaimer in the
  16. .\" documentation and/or other materials provided with the distribution.
  17. .\" 3. All advertising materials mentioning features or use of this software
  18. .\" must display the following acknowledgement:
  19. .\" This product includes software developed by the University of
  20. .\" California, Berkeley and its contributors.
  21. .\" 4. Neither the name of the University nor the names of its contributors
  22. .\" may be used to endorse or promote products derived from this software
  23. .\" without specific prior written permission.
  24. .\"
  25. .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  26. .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  27. .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  28. .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  29. .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  30. .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  31. .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  32. .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  33. .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  34. .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  35. .\" SUCH DAMAGE.
  36. .\"
  37. .\" from: @(#)strftime.3 5.12 (Berkeley) 6/29/91
  38. .\" $Id: strftime.3,v 1.4 1993/12/15 20:33:00 jtc Exp $
  39. .\"
  40. .TH NEWSTRFTIME 3
  41. .SH NAME
  42. strftime \- format date and time
  43. .SH SYNOPSIS
  44. .nf
  45. .B #include <sys/types.h>
  46. .B #include <time.h>
  47. .PP
  48. .B size_t strftime(buf, maxsize, format, timeptr)
  49. .B char *buf;
  50. .B size_t maxsize;
  51. .B const char *format;
  52. .B const struct tm *timeptr
  53. .PP
  54. .B cc ... -ltz
  55. .fi
  56. .SH DESCRIPTION
  57. The
  58. .I strftime\^
  59. function formats the information from
  60. .I timeptr\^
  61. into the buffer
  62. .I buf\^
  63. according to the string pointed to by
  64. .IR format\^ .
  65. .PP
  66. The
  67. .I format\^
  68. string consists of zero or more conversion specifications and
  69. ordinary characters.
  70. All ordinary characters are copied directly into the buffer.
  71. A conversion specification consists of a percent sign
  72. .Ql %
  73. and one other character.
  74. .PP
  75. No more than
  76. .I maxsize\^
  77. characters are be placed into the array.
  78. If the total number of resulting characters, including the terminating
  79. null character, is not more than
  80. .IR maxsize\^ ,
  81. .I strftime\^
  82. returns the number of characters in the array, not counting the
  83. terminating null.
  84. Otherwise, zero is returned.
  85. .PP
  86. Each conversion specification is replaced by the characters as
  87. follows which are then copied into the buffer.
  88. .TP
  89. %A
  90. is replaced by the locale's full weekday name.
  91. .TP
  92. %a
  93. is replaced by the locale's abbreviated weekday name.
  94. .TP
  95. %B
  96. is replaced by the locale's full month name.
  97. .TP
  98. %b or %h
  99. is replaced by the locale's abbreviated month name.
  100. .TP
  101. %C
  102. is replaced by the century (a year divided by 100 and truncated to an integer)
  103. as a decimal number (00-99).
  104. .TP
  105. %c
  106. is replaced by the locale's appropriate date and time representation.
  107. .TP
  108. %D
  109. is replaced by the date in the format %m/%d/%y.
  110. .TP
  111. %d
  112. is replaced by the day of the month as a decimal number (01-31).
  113. .TP
  114. %e
  115. is replaced by the day of month as a decimal number (1-31);
  116. single digits are preceded by a blank.
  117. .TP
  118. %F
  119. is replaced by the date in the format %Y-%m-%d.
  120. .TP
  121. %G
  122. is replaced by the ISO 8601 year with century as a decimal number.
  123. .TP
  124. %g
  125. is replaced by the ISO 8601 year without century as a decimal number (00-99).
  126. .TP
  127. %H
  128. is replaced by the hour (24-hour clock) as a decimal number (00-23).
  129. .TP
  130. %I
  131. is replaced by the hour (12-hour clock) as a decimal number (01-12).
  132. .TP
  133. %j
  134. is replaced by the day of the year as a decimal number (001-366).
  135. .TP
  136. %k
  137. is replaced by the hour (24-hour clock) as a decimal number (0-23);
  138. single digits are preceded by a blank.
  139. .TP
  140. %l
  141. is replaced by the hour (12-hour clock) as a decimal number (1-12);
  142. single digits are preceded by a blank.
  143. .TP
  144. %M
  145. is replaced by the minute as a decimal number (00-59).
  146. .TP
  147. %m
  148. is replaced by the month as a decimal number (01-12).
  149. .TP
  150. %n
  151. is replaced by a newline.
  152. .TP
  153. %p
  154. is replaced by the locale's equivalent of either AM or PM.
  155. .TP
  156. %R
  157. is replaced by the time in the format %H:%M.
  158. .TP
  159. %r
  160. is replaced by the locale's representation of 12-hour clock time
  161. using AM/PM notation.
  162. .TP
  163. %S
  164. is replaced by the second as a decimal number (00-60).
  165. .TP
  166. %s
  167. is replaced by the number of seconds since the Epoch, UTC (see mktime(3)).
  168. .TP
  169. %T
  170. is replaced by the time in the format %H:%M:%S.
  171. .TP
  172. %t
  173. is replaced by a tab.
  174. .TP
  175. %U
  176. is replaced by the week number of the year (Sunday as the first day of
  177. the week) as a decimal number (00-53).
  178. .TP
  179. %u
  180. is replaced by the weekday (Monday as the first day of the week)
  181. as a decimal number (1-7).
  182. .TP
  183. %V
  184. is replaced by the week number of the year (Monday as the first day of
  185. the week) as a decimal number (01-53). If the week containing January
  186. 1 has four or more days in the new year, then it is week 1; otherwise
  187. it is week 53 of the previous year, and the next week is week 1.
  188. .TP
  189. %W
  190. is replaced by the week number of the year (Monday as the first day of
  191. the week) as a decimal number (00-53).
  192. .TP
  193. %w
  194. is replaced by the weekday (Sunday as the first day of the week)
  195. as a decimal number (0-6).
  196. .TP
  197. %X
  198. is replaced by the locale's appropriate time representation.
  199. .TP
  200. %x
  201. is replaced by the locale's appropriate date representation.
  202. .TP
  203. %Y
  204. is replaced by the year with century as a decimal number.
  205. .TP
  206. %y
  207. is replaced by the year without century as a decimal number (00-99).
  208. .TP
  209. %Z
  210. is replaced by the time zone name,
  211. or by the empty string if this is not determinable.
  212. .TP
  213. %z
  214. is replaced by the offset from UTC in the format +HHMM or -HHMM as appropriate,
  215. with positive values representing locations east of Greenwich,
  216. or by the empty string if this is not determinable.
  217. .TP
  218. %%
  219. is replaced by a single %.
  220. .TP
  221. %+
  222. is replaced by the date and time in date(1) format.
  223. .SH SEE ALSO
  224. date(1),
  225. getenv(3),
  226. newctime(3),
  227. newtzset(3),
  228. time(2),
  229. tzfile(5)
  230. .\" %W%
  231. .\" This file is in the public domain, so clarified as of
  232. .\" 2009-05-17 by Arthur David Olson.