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.tr \(*W- . ds -- \(*W- . ds PI pi . if (\n(.H=4u)&(1m=24u) .ds -- \(*W\h'-12u'\(*W\h'-12u'-\" diablo 10 pitch . if (\n(.H=4u)&(1m=20u) .ds -- \(*W\h'-12u'\(*W\h'-8u'-\" diablo 12 pitch . ds L" "" . ds R" "" . ds C` "" . ds C' "" 'br\} . ds -- \|\(em\| . ds PI \(*p . ds L" `` . ds R" '' . ds C` . ds C' 'br\}
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Accent mark definitions (@(#)ms.acc 1.5 88/02/08 SMI; from UCB 4.2).
Fear. Run. Save yourself. No user-serviceable parts.
. \" fudge factors for nroff and troff . ds #H 0 . ds #V .8m . ds #F .3m . ds #[ \f1 . ds #] .\} . ds #H ((1u-(\\\\n(.fu%2u))*.13m) . ds #V .6m . ds #F 0 . ds #[ \& . ds #] \& .\} . \" simple accents for nroff and troff . ds ' \& . ds ` \& . ds ^ \& . ds , \& . ds ~ ~ . ds / .\} . ds ' \\k:\h'-(\\n(.wu*8/10-\*(#H)'\'\h"|\\n:u" . ds ` \\k:\h'-(\\n(.wu*8/10-\*(#H)'\`\h'|\\n:u' . ds ^ \\k:\h'-(\\n(.wu*10/11-\*(#H)'^\h'|\\n:u' . ds , \\k:\h'-(\\n(.wu*8/10)',\h'|\\n:u' . ds ~ \\k:\h'-(\\n(.wu-\*(#H-.1m)'~\h'|\\n:u' . ds / \\k:\h'-(\\n(.wu*8/10-\*(#H)'\z\(sl\h'|\\n:u' .\} . \" troff and (daisy-wheel) nroff accents . \" corrections for vroff . \" for low resolution devices (crt and lpr) \{\ . ds : e . ds 8 ss . ds o a . ds d- d\h'-1'\(ga . ds D- D\h'-1'\(hy . ds th \o'bp' . ds Th \o'LP' . ds ae ae . ds Ae AE .\} ========================================================================
Title "ASN1_TIME_set 3"
way too many mistakes in technical documents.
\fIASN1_TIME_adj() sets the \s-1ASN1_TIME\s0 structure s to the time represented by the time offset_day and offset_sec after the time_t value t. The values of offset_day or offset_sec can be negative to set a time before t. The offset_sec value can also exceed the number of seconds in a day. If s is \s-1NULL\s0 a new \s-1ASN1_TIME\s0 structure is allocated and returned.
\fIASN1_TIME_set_string() sets \s-1ASN1_TIME\s0 structure s to the time represented by string str which must be in appropriate \s-1ASN.1\s0 time format (for example \s-1YYMMDDHHMMSSZ\s0 or \s-1YYYYMMDDHHMMSSZ\s0).
\fIASN1_TIME_check() checks the syntax of \s-1ASN1_TIME\s0 structure s.
\fIASN1_TIME_print() prints out the time s to \s-1BIO \s0b in human readable format. It will be of the format \s-1MMM DD HH:MM:SS YYYY\s0 [\s-1GMT\s0], for example \*(L"Feb 3 00:55:52 2015 \s-1GMT\*(R"\s0 it does not include a newline. If the time structure has invalid format it prints out \*(L"Bad time value\*(R" and returns an error.
\fIASN1_TIME_diff() sets *pday and *psec to the time difference between \fBfrom and to. If to represents a time later than from then one or both (depending on the time difference) of *pday and *psec will be positive. If to represents a time earlier than from then one or both of *pday and *psec will be negative. If to and from represent the same time then *pday and *psec will both be zero. If both *pday and *psec are non-zero they will always have the same sign. The value of *psec will always be less than the number of seconds in a day. If from or to is \s-1NULL\s0 the current time is used.
The \s-1ASN1_TIME\s0 structure is represented as an \s-1ASN1_STRING\s0 internally and can be freed up using ASN1_STRING_free().
The \s-1ASN1_TIME\s0 structure can represent years from 0000 to 9999 but no attempt is made to correct ancient calendar changes (for example from Julian to Gregorian calendars).
Some applications add offset times directly to a time_t value and pass the results to ASN1_TIME_set() (or equivalent). This can cause problems as the time_t value can overflow on some systems resulting in unexpected results. New applications should use ASN1_TIME_adj() instead and pass the offset value in the offset_sec and offset_day parameters instead of directly manipulating a time_t value.
.Vb 11 #include <time.h> #include <openssl/asn1.h> ASN1_TIME *tm; time_t t; BIO *b; t = time(NULL); tm = ASN1_TIME_adj(NULL, t, 0, 60 * 60); b = BIO_new_fp(stdout, BIO_NOCLOSE); ASN1_TIME_print(b, tm); ASN1_STRING_free(tm); BIO_free(b); .Ve
Determine if one time is later or sooner than the current time:
.Vb 1 int day, sec; \& if (!ASN1_TIME_diff(&day, &sec, NULL, to)) /* Invalid time format */ \& if (day > 0 || sec > 0) printf("Later\en"); else if (day < 0 || sec < 0) printf("Sooner\en"); else printf("Same\en"); .Ve
\fIASN1_TIME_set_string() returns 1 if the time value is successfully set and 0 otherwise.
\fIASN1_TIME_check() returns 1 if the structure is syntactically correct and 0 otherwise.
\fIASN1_TIME_print() returns 1 if the time is successfully printed out and 0 if an error occurred (I/O error or invalid time format).
\fIASN1_TIME_diff() returns 1 for sucess and 0 for failure. It can fail if the pass \s-1ASN1_TIME\s0 structure has invalid syntax for example.