gettimeofday()

Get the current time

Synopsis:

#include <sys/time.h>

int gettimeofday( struct timeval * when,
                  void * not_used );

Arguments:

when
A pointer to a timeval structure where the function can store the time. The struct timeval contains the following members:
  • time_t tv_sec — the number of seconds since the start of the Unix Epoch.
  • suseconds_t tv_usec — the number of microseconds.
not_used
This pointer must be NULL or the behavior of gettimeofday() is undefined. This argument is provided only for backwards compatibility.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The gettimeofday() function returns the current time in when in seconds and microseconds, since the Unix Epoch, 00:00:00 January 1, 1970 Coordinated Universal Time (UTC) (formerly known as Greenwich Mean Time (GMT)).

Returns:

0 for success, or -1 if an error occurs (errno is set).

Errors:

EFAULT
An error occurred while accessing the when buffer.

Classification:

POSIX 1003.1 OB XSI. This function is marked as obsolescent, and may be removed from a future version of the standard.

Safety:  
Cancellation point No
Interrupt handler No
Signal handler Yes
Thread Yes

Caveats:

The gettimeofday() function is provided for porting existing code. You shouldn't use it in new code; use clock_gettime() instead.