Discussion :

[casier]

salut a tous,

ma question est simple : je voudrais savoir s'il existe un moyen simple (car je ne suis pas un expert en C) pour utiliser l'heure windows dans un programme C.
En fait, il me faudrait juste etre en mesure de lui faire faire "a telle heure tu fais...", donc je voudrais le mettre en attente jusqu'a ce que il soit xxh, auquel cas le programme fait sa petite affaire.

pourriez-vous m'aider ?

merci

[gege2061]

Bonjour,

voici un peu de lecture : gestion des dates et heures

Bon courrage

[miron]

Bien sur!!
Voici un petit reste d'un de mes programmes :

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struct tm {
  int tm_sec; /* secondes */
  int tm_min; /* minutes ( 0 -> 59 ) */
  int tm_hour; /* heure (0 -> 23 ) */
  int tm_mday; /* jour du mois (1 -> 31) */
  int tm_mon; /* mois ( 0 -> 11 ) */
  int tm_year; /* annee ( 1970 -> présent ) */
  int tm_wday; /* jour de la semaine ( di:0 -> sa:6 ) */
  int tm_yday; /* jour de l'année (1/1:0 -> 31/12:364) */
  int tm_isdst; /* lié à 'daylight saving time'-1 si sans objet; 1 si horaire d'été, 0 sinon */
  };

Deja tu definit ca et ensuite il te faudra surement :

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struct tm *pdh;
time_t intps;
intps=time(NULL);
pdh = localtime(&intps);

(a verifier)
Et voici un ex d'utilisation :

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if((pdh->tm_hour==heure)&&(pdh->tm_mday==jour))
{
...
}
//etc

Voila
+++

[casier]

oups, desole

merci beaucoup, je vais potasser ca alors !

PS : merci pour ta reponse miron

[Emmanuel Delahaye]

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struct tm {
  int tm_sec; /* secondes */
  int tm_min; /* minutes ( 0 -> 59 ) */
  int tm_hour; /* heure (0 -> 23 ) */
  int tm_mday; /* jour du mois (1 -> 31) */
  int tm_mon; /* mois ( 0 -> 11 ) */
  int tm_year; /* annee ( 1970 -> présent ) */
  int tm_wday; /* jour de la semaine ( di:0 -> sa:6 ) */
  int tm_yday; /* jour de l'année (1/1:0 -> 31/12:364) */
  int tm_isdst; /* lié à 'daylight saving time'-1 si sans objet; 1 si horaire d'été, 0 sinon */
  };

Deja tu definit ca

Tu définis quoi ? struct tm ? Pourquoi ? C'est du standard et c'est défini dans <time.h>.

[miron]

Tu définis quoi ? struct tm ? Pourquoi ? C'est du standard et c'est défini dans <time.h>.

ah bon...
Je savais pas...
et ca ?

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struct tm *pdh;
time_t intps;
intps=time(NULL);
pdh = localtime(&intps);

C'est defini aussi?

[Emmanuel Delahaye]

et ca ?

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struct tm *pdh;
time_t intps;
intps=time(NULL);
pdh = localtime(&intps);

C'est defini aussi?

Ben non. Ca, c'est une application. Ca n'a rien à voir. Tu parlais d'une structure...

[casier]

bon, j'ai l'impression que le tuto a quelques problèmes. Par exemple, je fais :

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   struct tm an2000;
   time_t th;
   an2000.tm_sec = 0;    /* 0 seconde */
   an2000.tm_min = 0;    /* 0 minute */
   an2000.tm_hour = 0;   /* 0 heure */
   an2000.tm_yday = 0;   /* 0 jour */
   an2000.tm_mon = 0;    /* 0 mois */
   an2000.tm_year = 100; /* 1900 + 100 annees */
   th=mktime(&an2000)
   printf("%s\n", ctime(&th));

et il me renvoie null...

je précise que le copier-coller de l'exemple de l'an 2000 ne marche pas, il renvoie une valeur fausse...

pourquoi ?

[miron]

bon, j'ai l'impression que le tuto a quelques problèmes. Par exemple, je fais :

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   struct tm an2000;
   time_t th;
   an2000.tm_sec = 0;    /* 0 seconde */
   an2000.tm_min = 0;    /* 0 minute */
   an2000.tm_hour = 0;   /* 0 heure */
   an2000.tm_yday = 0;   /* 0 jour */
   an2000.tm_mon = 0;    /* 0 mois */
   an2000.tm_year = 100; /* 1900 + 100 annees */
   th=mktime(&an2000)
   printf("%s\n", ctime(&th));

et il me renvoie null...

je précise que le copier-coller de l'exemple de l'an 2000 ne marche pas, il renvoie une valeur fausse...

pourquoi ?

Faudrais pas des accolades?
De plus je rapelle que http://www.developpez.net/forums/sho...24&postcount=3 fonctionne !

[casier]

des accolades ?? Ou ça ? Evidemment, ce code est inclu dans un main je ne l'ai pas précisé mais bon...
Puis j'ai essayé ton truc :

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struct tm *pdh;
    time_t intps;
    intps=time(NULL);
    pdh = localtime(&intps);
    if((pdh->tm_hour==20) && (pdh->tm_hmin==14))
    {
        printf("toto");
    }

et j'ai l'erreur de compilation : structure has no member named `tm_hmin'...(j'ai bien fait le include de time.h).

[miron]

des accolades ?? Ou ça ? Evidemment, ce code est inclu dans un main je ne l'ai pas précisé mais bon...
Puis j'ai essayé ton truc :

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struct tm *pdh;
    time_t intps;
    intps=time(NULL);
    pdh = localtime(&intps);
    if((pdh->tm_hour==20) && (pdh->tm_hmin==14))
    {
        printf("toto");
    }

et j'ai l'erreur de compilation : structure has no member named `tm_hmin'...(j'ai bien fait le include de time.h).

Je rapel ce qui est apparement inclu dans le time.h :

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struct tm {
  int tm_sec; /* secondes */
  int tm_min; /* minutes ( 0 -> 59 ) */
  int tm_hour; /* heure (0 -> 23 ) */
  int tm_mday; /* jour du mois (1 -> 31) */
  int tm_mon; /* mois ( 0 -> 11 ) */
  int tm_year; /* annee ( 1970 -> présent ) */
  int tm_wday; /* jour de la semaine ( di:0 -> sa:6 ) */
  int tm_yday; /* jour de l'année (1/1:0 -> 31/12:364) */
  int tm_isdst; /* lié à 'daylight saving time'-1 si sans objet; 1 si horaire d'été, 0 sinon */
  };

Comme tu peu le constater

tm_hmin

n'existe pas!!

[casier]

heuuuu, arf ! Bon, ça marche tu as raison !

En revanche, j'aimerai bien faire fonctionner le code cité au dessus, à savoir :

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struct tm an2000;
   time_t th;
   an2000.tm_sec = 0;    /* 0 seconde */
   an2000.tm_min = 0;    /* 0 minute */
   an2000.tm_hour = 0;   /* 0 heure */
   an2000.tm_yday = 0;   /* 0 jour */
   an2000.tm_mon = 0;    /* 0 mois */
   an2000.tm_year = 100; /* 1900 + 100 annees */
   th=mktime(&an2000)
   printf("%s\n", ctime(&th));

Tu as une idée de la raison pour laquelle il me renvoie "null"...?

[Emmanuel Delahaye]

En revanche, j'aimerai bien faire fonctionner le code cité au dessus, à savoir
Tu as une idée de la raison pour laquelle il me renvoie "null"...?

Ben oui, faut lire la doc... C'est pas tm_yday, mais tm_mday, et il ne doit pas valoir 0... D'autre part, les autres champs doivent être initialisés à 0...

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#include <stdio.h>
#include <time.h>
 
int main (void)
{
   struct tm an2000;
   time_t th = {0};
   an2000.tm_sec = 0;    /* 0 seconde */
   an2000.tm_min = 0;    /* 0 minute */
   an2000.tm_hour = 0;   /* 0 heure */
   an2000.tm_mday = 1;   /* 1 jour */
   an2000.tm_mon = 0;    /* 0 mois */
   an2000.tm_year = 100; /* 1900 + 100 annees */
   th = mktime(&an2000);
 
   {
      char *stime = ctime(&th);
      if (stime != NULL)
      {
         printf("%s\n", stime);
      }
      else
      {
         puts("NULL");
      }
   }
   return 0;
}

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Sat Jan 01 00:00:00 2000
 
 
Press ENTER to continue.

[casier]

pas besoin de dire ça sur ce ton, j'avais trouvé (bon c'est vrai que là j'ai fait la tête-à-claques ...).
En tout cas merci à tous, j'y suis arrivé.

[Emmanuel Delahaye]

Je rapel ce qui est apparement inclu dans le time.h :

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struct tm {
  int tm_sec; /* secondes */
  int tm_min; /* minutes ( 0 -> 59 ) */
  int tm_hour; /* heure (0 -> 23 ) */
  int tm_mday; /* jour du mois (1 -> 31) */
  int tm_mon; /* mois ( 0 -> 11 ) */
  int tm_year; /* annee ( 1970 -> présent ) */
  int tm_wday; /* jour de la semaine ( di:0 -> sa:6 ) */
  int tm_yday; /* jour de l'année (1/1:0 -> 31/12:364) */
  int tm_isdst; /* lié à 'daylight saving time'-1 si sans objet; 1 si horaire d'été, 0 sinon */
  };

Comment ça 'apparament' ? C'est la norme. Point.

ISO/IEC 9899:TC2 Committee Draft — May 6, 2005 WG14/N1124
7.23 Date and time <time.h>
7.23.1 Components of time
1 The header <time.h> defines two macros, and declares several types and functions for
manipulating time. Many functions deal with a calendar time that represents the current
date (according to the Gregorian calendar) and time. Some functions deal with local
time, which is the calendar time expressed for some specific time zone, and with Daylight
Saving Time, which is a temporary change in the algorithm for determining local time.
The local time zone and Daylight Saving Time are implementation-defined.
2 The macros defined are NULL (described in 7.17); and
CLOCKS_PER_SEC
which expands to an expression with type clock_t (described below) that is the
number per second of the value returned by the clock function.
3 The types declared are size_t (described in 7.17);
clock_t
and
time_t
which are arithmetic types capable of representing times; and
struct tm
which holds the components of a calendar time, called the broken-down time.
4 The range and precision of times representable in clock_t and time_t are
implementation-defined. The tm structure shall contain at least the following members,
in any order. The semantics of the members and their normal ranges are expressed in the
comments.268)
int tm_sec; // seconds after the minute — [0, 60]
int tm_min; // minutes after the hour — [0, 59]
int tm_hour; // hours since midnight — [0, 23]
int tm_mday; // day of the month — [1, 31]
int tm_mon; // months since January — [0, 11]
int tm_year; // years since 1900
int tm_wday; // days since Sunday — [0, 6]
int tm_yday; // days since January 1 — [0, 365]
int tm_isdst; // Daylight Saving Time flag
268) The range [0, 60] for tm_sec allows for a positive leap second.
338 Library §7.23.1

WG14/N1124 Committee Draft — May 6, 2005 ISO/IEC 9899:TC2
The value of tm_isdst is positive if Daylight Saving Time is in effect, zero if Daylight
Saving Time is not in effect, and negative if the information is not available.
7.23.2 Time manipulation functions
7.23.2.1 The clock function
Synopsis
1 #include <time.h>
clock_t clock(void);
Description
2 The clock function determines the processor time used.
Returns
3 The clock function returns the implementation’s best approximation to the processor
time used by the program since the beginning of an implementation-defined era related
only to the program invocation. To determine the time in seconds, the value returned by
the clock function should be divided by the value of the macro CLOCKS_PER_SEC. If
the processor time used is not available or its value cannot be represented, the function
returns the value (clock_t)(-1).269)
7.23.2.2 The difftime function
Synopsis
1 #include <time.h>
double difftime(time_t time1, time_t time0);
Description
2 The difftime function computes the difference between two calendar times: time1 -
time0.
Returns
3 The difftime function returns the difference expressed in seconds as a double.
269) In order to measure the time spent in a program, the clock function should be called at the start of
the program and its return value subtracted from the value returned by subsequent calls.
§7.23.2.2 Library 339

ISO/IEC 9899:TC2 Committee Draft — May 6, 2005 WG14/N1124
7.23.2.3 The mktime function
Synopsis
1 #include <time.h>
time_t mktime(struct tm *timeptr);
Description
2 The mktime function converts the broken-down time, expressed as local time, in the
structure pointed to by timeptr into a calendar time value with the same encoding as
that of the values returned by the time function. The original values of the tm_wday
and tm_yday components of the structure are ignored, and the original values of the
other components are not restricted to the ranges indicated above.270) On successful
completion, the values of the tm_wday and tm_yday components of the structure are
set appropriately, and the other components are set to represent the specified calendar
time, but with their values forced to the ranges indicated above; the final value of
tm_mday is not set until tm_mon and tm_year are determined.
Returns
3 The mktime function returns the specified calendar time encoded as a value of type
time_t. If the calendar time cannot be represented, the function returns the value
(time_t)(-1).
4 EXAMPLE What day of the week is July 4, 2001?
#include <stdio.h>
#include <time.h>
static const char *const wday[] = {
"Sunday", "Monday", "Tuesday", "Wednesday",
"Thursday", "Friday", "Saturday", "-unknown-"
};
struct tm time_str;
/* ... */
270) Thus, a positive or zero value for tm_isdst causes the mktime function to presume initially that
Daylight Saving Time, respectively, is or is not in effect for the specified time. A neg ative value
causes it to attempt to determine whether Daylight Saving Time is in effect for the specified time.
340 Library §7.23.2.3

WG14/N1124 Committee Draft — May 6, 2005 ISO/IEC 9899:TC2
time_str.tm_year = 2001 - 1900;
time_str.tm_mon = 7 - 1;
time_str.tm_mday = 4;
time_str.tm_hour = 0;
time_str.tm_min = 0;
time_str.tm_sec = 1;
time_str.tm_isdst = -1;
if (mktime(&time_str) == (time_t)(-1))
time_str.tm_wday = 7;
printf("%s\n", wday[time_str.tm_wday]);
7.23.2.4 The time function
Synopsis
1 #include <time.h>
time_t time(time_t *timer);
Description
2 The time function determines the current calendar time. The encoding of the value is
unspecified.
Returns
3 The time function returns the implementation’s best approximation to the current
calendar time. The value (time_t)(-1) is returned if the calendar time is not
available. If timer is not a null pointer, the return value is also assigned to the object it
points to.
7.23.3 Time conversion functions
1 Except for the strftime function, these functions each return a pointer to one of two
types of static objects: a broken-down time structure or an array of char. Execution of
any of the functions that return a pointer to one of these object types may overwrite the
information in any object of the same type pointed to by the value returned from any
previous call to any of them. The implementation shall behave as if no other library
functions call these functions.
7.23.3.1 The asctime function
Synopsis
1 #include <time.h>
char *asctime(const struct tm *timeptr);
Description
2 The asctime function converts the broken-down time in the structure pointed to by
timeptr into a string in the form
Sun Sep 16 01:03:52 1973\n\0
§7.23.3.1 Library 341

ISO/IEC 9899:TC2 Committee Draft — May 6, 2005 WG14/N1124
using the equivalent of the following algorithm.
char *asctime(const struct tm *timeptr)
{
static const char wday_name[7][3] = {
"Sun", "Mon", "Tue", "Wed", "Thu", "Fri", "Sat"
};
static const char mon_name[12][3] = {
"Jan", "Feb", "Mar", "Apr", "May", "Jun",
"Jul", "Aug", "Sep", "Oct", "Nov", "Dec"
};
static char result[26];
sprintf(result, "%.3s %.3s%3d %.2d:%.2d:%.2d %d\n",
wday_name[timeptr->tm_wday],
mon_name[timeptr->tm_mon],
timeptr->tm_mday, timeptr->tm_hour,
timeptr->tm_min, timeptr->tm_sec,
1900 + timeptr->tm_year);
return result;
}
Returns
3 The asctime function returns a pointer to the string.
7.23.3.2 The ctime function
Synopsis
1 #include <time.h>
char *ctime(const time_t *timer);
Description
2 The ctime function converts the calendar time pointed to by timer to local time in the
form of a string. It is equivalent to
asctime(localtime(timer))
Returns
3 The ctime function returns the pointer returned by the asctime function with that
broken-down time as argument.
Forward references: the localtime function (7.23.3.4).
342 Library §7.23.3.2

WG14/N1124 Committee Draft — May 6, 2005 ISO/IEC 9899:TC2
7.23.3.3 The gmtime function
Synopsis
1 #include <time.h>
struct tm *gmtime(const time_t *timer);
Description
2 The gmtime function converts the calendar time pointed to by timer into a brokendown
time, expressed as UTC.
Returns
3 The gmtime function returns a pointer to the broken-down time, or a null pointer if the
specified time cannot be converted to UTC.
7.23.3.4 The localtime function
Synopsis
1 #include <time.h>
struct tm *localtime(const time_t *timer);
Description
2 The localtime function converts the calendar time pointed to by timer into a
broken-down time, expressed as local time.
Returns
3 The localtime function returns a pointer to the broken-down time, or a null pointer if
the specified time cannot be converted to local time.
7.23.3.5 The strftime function
Synopsis
1 #include <time.h>
size_t strftime(char * restrict s,
size_t maxsize,
const char * restrict format,
const struct tm * restrict timeptr);
Description
2 The strftime function places characters into the array pointed to by s as controlled by
the string pointed to by format. The format shall be a multibyte character sequence,
beginning and ending in its initial shift state. The format string consists of zero or
more conversion specifiers and ordinary multibyte characters. A conversion specifier
consists of a % character, possibly followed by an E or O modifier character (described
below), followed by a character that determines the behavior of the conversion specifier.
All ordinary multibyte characters (including the terminating null character) are copied
§7.23.3.5 Library 343

ISO/IEC 9899:TC2 Committee Draft — May 6, 2005 WG14/N1124
unchanged into the array. If copying takes place between objects that overlap, the
behavior is undefined. No more than maxsize characters are placed into the array.
3 Each conversion specifier is replaced by appropriate characters as described in the
following list. The appropriate characters are determined using the LC_TIME category
of the current locale and by the values of zero or more members of the broken-down time
structure pointed to by timeptr, as specified in brackets in the description. If any of
the specified values is outside the normal range, the characters stored are unspecified.
%a is replaced by the locale’s abbreviated weekday name. [tm_wday]
%A is replaced by the locale’s full weekday name. [tm_wday]
%b is replaced by the locale’s abbreviated month name. [tm_mon]
%B is replaced by the locale’s full month name. [tm_mon]
%c is replaced by the locale’s appropriate date and time representation. [all specified
in 7.23.1]
%C is replaced by the year divided by 100 and truncated to an integer, as a decimal
number (00−99). [tm_year]
%d is replaced by the day of the month as a decimal number (01−31). [tm_mday]
%D is equivalent to ‘‘%m/%d/%y’’. [tm_mon, tm_mday, tm_year]
%e is replaced by the day of the month as a decimal number (1−31); a single digit is
preceded by a space. [tm_mday]
%F is equivalent to ‘‘%Y−%m−%d’’ (the ISO 8601 date format). [tm_year, tm_mon,
tm_mday]
%g is replaced by the last 2 digits of the week-based year (see below) as a decimal
number (00−99). [tm_year, tm_wday, tm_yday]
%G is replaced by the week-based year (see below) as a decimal number (e.g., 1997).
[tm_year, tm_wday, tm_yday]
%h is equivalent to ‘‘%b’’. [tm_mon]
%H is replaced by the hour (24-hour clock) as a decimal number (00−23). [tm_hour]
%I is replaced by the hour (12-hour clock) as a decimal number (01−12). [tm_hour]
%j is replaced by the day of the year as a decimal number (001−366). [tm_yday]
%m is replaced by the month as a decimal number (01−12). [tm_mon]
%M is replaced by the minute as a decimal number (00−59). [tm_min]
%n is replaced by a new-line character.
%p is replaced by the locale’s equivalent of the AM/PM designations associated with a
12-hour clock. [tm_hour]
%r is replaced by the locale’s 12-hour clock time. [tm_hour, tm_min, tm_sec]
%R is equivalent to ‘‘%H:%M’’. [tm_hour, tm_min]
%S is replaced by the second as a decimal number (00−60). [tm_sec]
%t is replaced by a horizontal-tab character.
%T is equivalent to ‘‘%H:%M:%S’’ (the ISO 8601 time format). [tm_hour, tm_min,
tm_sec]
344 Library §7.23.3.5

WG14/N1124 Committee Draft — May 6, 2005 ISO/IEC 9899:TC2
%u is replaced by the ISO 8601 weekday as a decimal number (1−7), where Monday
is 1. [tm_wday]
%U is replaced by the week number of the year (the first Sunday as the first day of week
1) as a decimal number (00−53). [tm_year, tm_wday, tm_yday]
%V is replaced by the ISO 8601 week number (see below) as a decimal number
(01−53). [tm_year, tm_wday, tm_yday]
%w is replaced by the weekday as a decimal number (0−6), where Sunday is 0.
[tm_wday]
%W is replaced by the week number of the year (the first Monday as the first day of
week 1) as a decimal number (00−53). [tm_year, tm_wday, tm_yday]
%x is replaced by the locale’s appropriate date representation. [all specified in 7.23.1]
%X is replaced by the locale’s appropriate time representation. [all specified in 7.23.1]
%y is replaced by the last 2 digits of the year as a decimal number (00−99).
[tm_year]
%Y is replaced by the year as a decimal number (e.g., 1997). [tm_year]
%z is replaced by the offset from UTC in the ISO 8601 format ‘‘−0430’’ (meaning 4
hours 30 minutes behind UTC, west of Greenwich), or by no characters if no time
zone is determinable. [tm_isdst]
%Z is replaced by the locale’s time zone name or abbreviation, or by no characters if no
time zone is determinable. [tm_isdst]
%% is replaced by %.
4 Some conversion specifiers can be modified by the inclusion of an E or O modifier
character to indicate an alternative format or specification. If the alternative format or
specification does not exist for the current locale, the modifier is ignored.
%Ec is replaced by the locale’s alternative date and time representation.
%EC is replaced by the name of the base year (period) in the locale’s alternative
representation.
%Ex is replaced by the locale’s alternative date representation.
%EX is replaced by the locale’s alternative time representation.
%Ey is replaced by the offset from %EC (year only) in the locale’s alternative
representation.
%EY is replaced by the locale’s full alternative year representation.
%Od is replaced by the day of the month, using the locale’s alternative numeric symbols
(filled as needed with leading zeros, or with leading spaces if there is no alternative
symbol for zero).
%Oe is replaced by the day of the month, using the locale’s alternative numeric symbols
(filled as needed with leading spaces).
%OH is replaced by the hour (24-hour clock), using the locale’s alternative numeric
symbols.
§7.23.3.5 Library 345

ISO/IEC 9899:TC2 Committee Draft — May 6, 2005 WG14/N1124
%OI is replaced by the hour (12-hour clock), using the locale’s alternative numeric
symbols.
%Om is replaced by the month, using the locale’s alternative numeric symbols.
%OM is replaced by the minutes, using the locale’s alternative numeric symbols.
%OS is replaced by the seconds, using the locale’s alternative numeric symbols.
%Ou is replaced by the ISO 8601 weekday as a number in the locale’s alternative
representation, where Monday is 1.
%OU is replaced by the week number, using the locale’s alternative numeric symbols.
%OV is replaced by the ISO 8601 week number, using the locale’s alternative numeric
symbols.
%Ow is replaced by the weekday as a number, using the locale’s alternative numeric
symbols.
%OW is replaced by the week number of the year, using the locale’s alternative numeric
symbols.
%Oy is replaced by the last 2 digits of the year, using the locale’s alternative numeric
symbols.
5 %g, %G, and %V give values according to the ISO 8601 week-based year. In this system,
weeks begin on a Monday and week 1 of the year is the week that includes January 4th,
which is also the week that includes the first Thursday of the year, and is also the first
week that contains at least four days in the year. If the first Monday of January is the
2nd, 3rd, or 4th, the preceding days are part of the last week of the preceding year; thus,
for Saturday 2nd January 1999, %G is replaced by 1998 and %V is replaced by 53. If
December 29th, 30th, or 31st is a Monday, it and any following days are part of week 1 of
the following year. Thus, for Tuesday 30th December 1997, %G is replaced by 1998 and
%V is replaced by 01.
6 If a conversion specifier is not one of the above, the behavior is undefined.
7 In the "C" locale, the E and O modifiers are ignored and the replacement strings for the
following specifiers are:
%a the first three characters of %A.
%A one of ‘‘Sunday’’, ‘‘Monday’’, ... , ‘‘Saturday’’.
%b the first three characters of %B.
%B one of ‘‘January’’, ‘‘February’’, ... , ‘‘December’’.
%c equivalent to ‘‘%a %b %e %T %Y’’.
%p one of ‘‘AM’’ or ‘‘PM’’.
%r equivalent to ‘‘%I:%M:%S %p’’.
%x equivalent to ‘‘%m/%d/%y’’.
%X equivalent to %T.
%Z implementation-defined.
346 Library §7.23.3.5

WG14/N1124 Committee Draft — May 6, 2005 ISO/IEC 9899:TC2
Returns
8 If the total number of resulting characters including the terminating null character is not
more than maxsize, the strftime function returns the number of characters placed
into the array pointed to by s not including the terminating null character. Otherwise,
zero is returned and the contents of the array are indeterminate.
§7.23.3.5 Library 347

[miron]

Comment ça 'apparament' ? C'est la norme. Point.

Je ne l'avais jamais verifié.point.
(dabord je n'airais pas su ou chercher...)
Et puis c'est quoi tout ce charabia ?
Cela sort d'une page ?
Le passage

ISO/IEC 9899:TC2 Committee Draft — May 6, 2005 WG14/N1124
7.23 Date and time <time.h>
7.23.1 Components of time
1 The header <time.h> defines two macros, and declares several types and functions for
manipulating time. Many functions deal with a calendar time that represents the current
date (according to the Gregorian calendar) and time. Some functions deal with local
time, which is the calendar time expressed for some specific time zone, and with Daylight
Saving Time, which is a temporary change in the algorithm for determining local time.
The local time zone and Daylight Saving Time are implementation-defined.
2 The macros defined are NULL (described in 7.17); and
CLOCKS_PER_SEC
which expands to an expression with type clock_t (described below) that is the
number per second of the value returned by the clock function.
3 The types declared are size_t (described in 7.17);
clock_t
and
time_t
which are arithmetic types capable of representing times; and
struct tm
which holds the components of a calendar time, called the broken-down time.
4 The range and precision of times representable in clock_t and time_t are
implementation-defined. The tm structure shall contain at least the following members,
in any order. The semantics of the members and their normal ranges are expressed in the
comments.268)
int tm_sec; // seconds after the minute — [0, 60]
int tm_min; // minutes after the hour — [0, 59]
int tm_hour; // hours since midnight — [0, 23]
int tm_mday; // day of the month — [1, 31]
int tm_mon; // months since January — [0, 11]
int tm_year; // years since 1900
int tm_wday; // days since Sunday — [0, 6]
int tm_yday; // days since January 1 — [0, 365]
int tm_isdst; // Daylight Saving Time flag

M'aurais sufit je pensse...

[Emmanuel Delahaye]

Je ne l'avais jamais verifié.

C'est un tord.

(dabord je n'airais pas su ou chercher...)

Encore plus grave

• Ton livre de C
• Les pages man de developpez : http://man.developpez.com/
• La norme : http://www.open-std.org/JTC1/SC22/WG...docs/n1124.pdf (référence sur mon site...)

Et puis c'est quoi tout ce charabia ?

C'est la norme. J'ai mis tout le passage sur les fonctions <time.h> puisque tu as l'air de ne pas les connaitre... Désolé d'essayer de t'aider...

[miron]

Désolé d'essayer de t'aider...

Non mais je vous remerci, c'est tres gentil !!

[nicolas66]

Ouch, ya de l'eau dans le gaz ici