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36 .\" $FreeBSD: src/lib/libc/stdtime/strftime.3,v 1.18.2.10 2003/05/24 00:01:31 keramida Exp $
43 .Nd format date and time
50 .Fa "char * restrict buf"
52 .Fa "const char * restrict format"
53 .Fa "const struct tm * restrict timeptr"
58 function formats the information from
62 according to the string pointed to by
67 string consists of zero or more conversion specifications and
69 All ordinary characters are copied directly into the buffer.
70 A conversion specification consists of a percent sign
72 and one other character.
76 characters will be placed into the array.
77 If the total number of resulting characters, including the terminating
78 NUL character, is not more than
81 returns the number of characters in the array, not counting the
83 Otherwise, zero is returned and the buffer contents are indeterminate.
85 The conversion specifications are copied to the buffer after expansion
87 .Bl -tag -width "xxxx"
89 is replaced by national representation of the full weekday name.
91 is replaced by national representation of
92 the abbreviated weekday name.
94 is replaced by national representation of the full month name.
96 is replaced by national representation of
97 the abbreviated month name.
99 is replaced by (year / 100) as decimal number; single
100 digits are preceded by a zero.
102 is replaced by national representation of time and date.
107 is replaced by the day of the month as a decimal number (01-31).
108 .It Cm \&%E* Cm \&%O*
109 POSIX locale extensions.
111 %Ec %EC %Ex %EX %Ey %EY
112 %Od %Oe %OH %OI %Om %OM
113 %OS %Ou %OU %OV %Ow %OW %Oy
114 are supposed to provide alternate
117 Additionally %OB implemented
118 to represent alternative months names
119 (used standalone, without day mentioned).
121 is replaced by the day of month as a decimal number (1-31); single
122 digits are preceded by a blank.
124 is replaced by the date in the format
127 is replaced by a year as a decimal number with century.
128 This year is the one that contains the greater part of
129 the week (Monday as the first day of the week).
131 is replaced by the same year as in
133 but as a decimal number without century (00-99).
135 is replaced by the hour (24-hour clock) as a decimal number (00-23).
139 is replaced by the hour (12-hour clock) as a decimal number (01-12).
141 is replaced by the day of the year as a decimal number (001-366).
143 is replaced by the hour (24-hour clock) as a decimal number (0-23);
144 single digits are preceded by a blank.
146 is replaced by the hour (12-hour clock) as a decimal number (1-12);
147 single digits are preceded by a blank.
149 is replaced by the minute as a decimal number (00-59).
151 is replaced by the month as a decimal number (01-12).
153 is replaced by a newline.
157 is replaced by national representation of either
169 is replaced by the second as a decimal number (00-60).
171 is replaced by the number of seconds since the Epoch, UTC (see
177 is replaced by a tab.
179 is replaced by the week number of the year (Sunday as the first day of
180 the week) as a decimal number (00-53).
182 is replaced by the weekday (Monday as the first day of the week)
183 as a decimal number (1-7).
185 is replaced by the week number of the year (Monday as the first day of
186 the week) as a decimal number (01-53). If the week containing January
187 1 has four or more days in the new year, then it is week 1; otherwise
188 it is the last week of the previous year, and the next week is week 1.
193 is replaced by the week number of the year (Monday as the first day of
194 the week) as a decimal number (00-53).
196 is replaced by the weekday (Sunday as the first day of the week)
197 as a decimal number (0-6).
199 is replaced by national representation of the time.
201 is replaced by national representation of the date.
203 is replaced by the year with century as a decimal number.
205 is replaced by the year without century as a decimal number (00-99).
207 is replaced by the time zone name,
208 or by the empty string if this is not determinable.
210 is replaced by the offset from UTC in the format
215 with positive values representing locations east of Greenwich,
216 or by the empty string if this is not determinable.
218 is replaced by national representation of the date and time
219 (the format is similar to that produced by
237 with a lot of extensions including
259 The peculiar week number and year in the replacements of
264 are defined in ISO 8601: 1988.
266 There is no conversion specification for the phase of the moon.