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gettimeofday(3ucb) [sunos man page]

gettimeofday(3UCB)				     SunOS/BSD Compatibility Library Functions					gettimeofday(3UCB)

NAME
gettimeofday, settimeofday - get or set the date and time SYNOPSIS
/usr/ucb/cc[ flag ... ] file ... #include <sys/time.h> int gettimeofday( tp, tzp); struct timeval *tzp; struct timezone *tzp; int settimeofday( tp, tzp); struct timeval *tzp; struct timezone *tzp; DESCRIPTION
The system's notion of the current Greenwich time is obtained with the gettimeofday() call, and set with the settimeofday() call. The cur- rent time is expressed in elapsed seconds and microseconds since 00:00 GMT, January 1, 1970 (zero hour). The resolution of the system clock is hardware dependent; the time may be updated continuously, or in clock ticks. long tv_sec; /* seconds since Jan. 1, 1970 */ long tv_usec; /* and microseconds */ tp points to a timeval structure, which includes the following members: If tp is a NULL pointer, the current time information is not returned or set. tzp is an obsolete pointer formerly used to get and set timezone information. tzp is now ignored. Timezone information is now handled using the TZ environment variable; see TIMEZONE(4). Only the privileged user may set the time of day. RETURN VALUES
A -1 return value indicates an error occurred; in this case an error code is stored in the global variable errno. ERRORS
The following error codes may be set in errno: EINVAL tp specifies an invalid time. EPERM A user other than the privileged user attempted to set the time. SEE ALSO
adjtime(2), ctime(3C), gettimeofday(3C), TIMEZONE(4) NOTES
Use of these interfaces should be restricted to only applications written on BSD platforms. Use of these interfaces with any of the system libraries or in multi-thread applications is unsupported. tzp is ignored in SunOS 5.X releases. tv_usec is always 0. SunOS 5.10 18 Feb 1993 gettimeofday(3UCB)

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gettimeofday(3C)					   Standard C Library Functions 					  gettimeofday(3C)

NAME
gettimeofday, settimeofday - get or set the date and time SYNOPSIS
#include <sys/time.h> int gettimeofday(struct timeval *tp, void *tzp); int settimeofday(struct timeval *tp, void *tzp); DESCRIPTION
The gettimeofday() function gets and the settimeofday() function sets the system's notion of the current time. The current time is expressed in elapsed seconds and microseconds since 00:00 Universal Coordinated Time, January 1, 1970. The resolution of the system clock is hardware dependent; the time may be updated continuously or in clock ticks. The tp argument points to a timeval structure, which includes the following members: long tv_sec; /* seconds since Jan. 1, 1970 */ long tv_usec; /* and microseconds */ If tp is a null pointer, the current time information is not returned or set. The TZ environment variable holds time zone information. See TIMEZONE(4). The tzp argument to gettimeofday() and settimeofday() is ignored. Only privileged processes can set the time of day. RETURN VALUES
Upon successful completion, 0 is returned. Otherwise, -1 is returned and errno is set to indicate the error. ERRORS
The settimeofday() function will fail if: EINVAL The structure pointed to by tp specifies an invalid time. EPERM The {PRIV_SYS_TIME} privilege was not asserted in the effective set of the calling process. The gettimeofday() function will fail for 32-bit interfaces if: EOVERFLOW The system time has progressed beyond 2038, thus the size of the tv_sec member of the timeval structure pointed to by tp is insufficient to hold the current time in seconds. USAGE
If the tv_usec member of tp is > 500000, settimeofday() rounds the seconds upward. If the time needs to be set with better than one second accuracy, call settimeofday() for the seconds and then adjtime(2) for finer accuracy. ATTRIBUTES
See attributes(5) for descriptions of the following attributes: +-----------------------------+-----------------------------+ | ATTRIBUTE TYPE | ATTRIBUTE VALUE | +-----------------------------+-----------------------------+ |Interface Stability |gettimeofday() is Standard. | +-----------------------------+-----------------------------+ |MT-Level |MT-Safe | +-----------------------------+-----------------------------+ SEE ALSO
adjtime(2), ctime(3C), gethrtime(3C), TIMEZONE(4), attributes(5), privileges(5), standards(5) SunOS 5.11 1 Aug 2003 gettimeofday(3C)
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