Name
ctime
Synopsis
Converts an integer time value into a date and time string
#include <time.h> char *ctime
( const time_t *seconds
);
The argument passed to the ctime()
function is a pointer to a number
interpreted as a number of seconds elapsed since the epoch (on Unix
systems, January 1, 1970).
The function converts this value into a human-readable character string showing the local date and time, and returns a pointer to that string. The string is exactly 26 bytes long, including the terminating null character, and has the following format:
Thu Apr 28 15:50:56 2005\n
The argument’s type, time_t
, is defined in time.h, usually as a long
or unsigned
long
integer.
The function call ctime(&
seconds
)
is equivalent to asctime(localtime(&
seconds
))
. A common way to obtain the argument
value passed to ctime()
is by
calling the time()
function,
which returns the current time in seconds.
Example
void logerror(int errorcode)
{
time_t eventtime;
time(&eventtime);
fprintf( stderr, "%s: Error number %d occurred.\n",ctime
(&eventtime), errorcode );
}
This code produces output like the following:
Fri Sep 9 14:58:03 2005 : Error number 23 occurred.
The output contains a line break because the string produced
by ctime()
ends in a newline
character.
See Also
asctime()
, difftime()
, gmtime()
, localtime()
, mktime()
, strftime()
, time()
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