asctime, asctime_r
![]() |
![]() |
![]() |
![]() |
asctime(), asctime_r()
Convert time information to a string
Synopsis:
#include <time.h>
char* asctime( const struct tm* timeptr );
char* asctime_r( const struct tm* timeptr,
char* buf );
Arguments:
- timeptr
- A pointer to a tm structure that contains the time that you want to convert to a string.
- buf
- (asctime_r() only) A buffer in which asctime_r() can store the resulting string. This buffer must be large enough to hold at least 26 characters.
Library:
libc
Use the -l c option to qcc to link against this library. This library is usually included automatically.
Description:
The asctime() and asctime_r() functions convert the time information in the structure pointed to by timeptr into a string containing exactly 26 characters, in the form:
Tue May 7 10:40:27 2002\n\0
![]() |
The asctime() function places the result string in a static
buffer that's reused every time you call asctime() or
ctime().
Calling
gmtime()
or
localtime()
could also change the date in this static buffer.
The result string for asctime_r() is contained in the buffer pointed to by buf. |
All fields have a constant width. The newline character ('\n') and a NUL character ('\0') occupy the last two positions of the string.
Returns:
A pointer to the character string result, or NULL if an error occurred.
Classification:
asctime() is ANSI, POSIX 1003.1; asctime_r() is POSIX 1003.1 TSF
asctime()
| Safety: | |
|---|---|
| Cancellation point | No |
| Interrupt handler | No |
| Signal handler | No |
| Thread | No |
asctime_r()
| Safety: | |
|---|---|
| Cancellation point | No |
| Interrupt handler | No |
| Signal handler | Yes |
| Thread | Yes |
Caveats:
The asctime() and ctime() functions place their results in a static buffer that's reused for each call to asctime() or ctime().
See also:
clock(), ctime(), difftime(), gmtime(), localtime(), localtime_r(), mktime(), strftime(), time(), tm, tzset()
![]() |
![]() |
![]() |
![]() |

![[Previous]](../prev.gif)
![[Contents]](../contents.gif)
![[Index]](../keyword_index.gif)
![[Next]](../next.gif)

