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 unspecified. 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 XSI

Caveats:

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

See also:

asctime(), asctime_r(), clock_gettime(), clock_settime(), ctime(), ctime_r(), difftime(), gmtime(), gmtime_r(), localtime(), localtime_r(), settimeofday(), time()