epicsTime Class Reference

C++ time stamp object. More...

#include <epicsTime.h>

Public Types
typedef std::runtime_error	unableToFetchCurrentTime
	Exception: Time provider problem.
typedef std::logic_error	formatProblemWithStructTM
	Exception: Bad field(s) in struct tm

Public Member Functions
	epicsTime ()
	The default constructor sets the time to the EPICS epoch.
size_t	strftime (char *pBuff, size_t bufLength, const char *pFormat) const
	Convert to string in user-specified format. More...
void	show (unsigned interestLevel) const
	Dump current state to standard out.
epicsTimeStamp conversions
Convert to and from EPICS epicsTimeStamp format
	operator const epicsTimeStamp & () const
	Convert to epicsTimeStamp.
	epicsTime (const epicsTimeStamp &replace)
	Construct from epicsTimeStamp.
epicsTime &	operator= (const epicsTimeStamp &replace)
	Assign from epicsTimeStamp.
ANSI C time_t conversions
Convert to and from ANSI C time_t wrapper .
	operator time_t_wrapper () const
	Convert to ANSI C time_t.
	epicsTime (const time_t_wrapper &replace)
	Construct from ANSI C time_t.
epicsTime &	operator= (const time_t_wrapper &replace)
	Assign from ANSI C time_t.
ANSI C struct tm local-time conversions
Convert to and from ANSI Cs struct tm (with nano seconds), adjusted for the local time zone.
	operator local_tm_nano_sec () const
	Convert to struct tm in local time zone.
	epicsTime (const local_tm_nano_sec &replace)
	Construct from struct tm in local time zone.
epicsTime &	operator= (const local_tm_nano_sec &replace)
	Assign from struct tm in local time zone.
ANSI C struct tm UTC conversions
Convert to and from ANSI Cs struct tm (with nano seconds), adjusted for Greenwich Mean Time (UTC).
	operator gm_tm_nano_sec () const
	Convert to struct tm in UTC/GMT.
	epicsTime (const gm_tm_nano_sec &replace)
	Construct from struct tm in UTC/GMT.
epicsTime &	operator= (const gm_tm_nano_sec &replace)
	Assign from struct tm in UTC.
POSIX RT struct timespec conversions
Convert to and from the POSIX RealTime struct timespec format.
	operator struct timespec () const
	Convert to struct timespec
	epicsTime (const struct timespec &replace)
	Construct from struct timespec
epicsTime &	operator= (const struct timespec &replace)
	Assign from struct timespec
BSD's struct timeval conversions
Convert to and from the BSD struct timeval format.
	operator struct timeval () const
	Convert to struct timeval
	epicsTime (const struct timeval &replace)
	Construct from struct timeval
epicsTime &	operator= (const struct timeval &replace)
	Assign from struct timeval
Arithmetic operators
Standard operators involving epicsTime objects and time differences which are always expressed as a double in seconds.
double	operator- (const epicsTime &other) const
	lhs minus rhs, in seconds
epicsTime	operator+ (double delta) const
	lhs plus rhs seconds
epicsTime	operator- (double delta) const
	lhs minus rhs seconds
epicsTime	operator+= (double delta)
	add rhs seconds to lhs
epicsTime	operator-= (double delta)
	subtract rhs seconds from lhs
Comparison operators
Standard comparisons between epicsTime objects.
bool	operator== (const epicsTime &other) const
	lhs equals rhs
bool	operator!= (const epicsTime &other) const
	lhs not equal to rhs
bool	operator<= (const epicsTime &other) const
	rhs no later than lhs
bool	operator< (const epicsTime &other) const
	lhs was before rhs
bool	operator>= (const epicsTime &other) const
	rhs not before lhs
bool	operator> (const epicsTime &other) const
	lhs was after rhs

Static Public Member Functions
static epicsTime	getEvent (const epicsTimeEvent &evt)
	Get time of event system event. More...
static epicsTime	getCurrent ()
	Get current clock time. More...
static epicsTime	getMonotonic ()
	Get current monotonic time. More...

Detailed Description

Holds an EPICS time stamp, and provides conversion functions for both input and output from/to other types.

Note

Time conversions: The epicsTime implementation will properly convert between the various formats from the beginning of the EPICS epoch until at least 2038. Unless the underlying architecture support has defective POSIX, BSD/SRV5, or standard C time support the EPICS implementation should be valid until 2106.

Definition at line 320 of file epicsTime.h.

Member Function Documentation

static epicsTime epicsTime::getEvent ( const epicsTimeEvent &  evt )

inlinestatic

Returns an epicsTime indicating when the associated event system event last occurred.

static epicsTime epicsTime::getCurrent ( )

static

Returns an epicsTime containing the current time. For example:

epicsTime now = epicsTime::getCurrent();

static epicsTime epicsTime::getMonotonic ( )

inlinestatic

Returns an epicsTime containing the current monotonic time, an OS clock which never going backwards or jumping forwards. This time is has an undefined epoch, and is only useful for measuring time differences.

Definition at line 360 of file epicsTime.h.

size_t epicsTime::strftime ( char *  pBuff, size_t  bufLength, const char *  pFormat  ) const

inline

This method extends the standard C library routine strftime(). See your OS documentation for details about the standard routine. The epicsTime method adds support for printing the fractional portion of the time. It searches the format string for the sequence %0nf where n is the desired precision, and uses this format to convert the fractional seconds with the requested precision. For example:

epicsTime time = epicsTime::getCurrent();
char buf[30];
time.strftime(buf, 30, "%Y-%m-%d %H:%M:%S.%06f");
printf("%s\n", buf);

This will print the current time in the format:

2001-01-26 20:50:29.813505

Definition at line 568 of file epicsTime.h.

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The documentation for this class was generated from the following file:

• epicsTime.h