PGI Fortran Reference manual - The Portland Group

3F Functions and VAX Subroutineswhere (REAL or DOUBLE PRECISION) y is set equal to the time in seconds since midnight,minus the user supplied value of the (REAL or DOUBLE PRECISION) x. Elapsed timecomputations can be performed with the following sequence of calls.X = SECNDS(0.0)...... ! Code to be timed...DELTA = SECNDS(X)The accuracy of this call is the same as the resolution of the system clock.TIMEThe TIME subroutine returns the current system time as an ASCII string. It has the form:CALL TIME(buf)where buf is an eight-byte variable, array, array element, or character substring. The TIME callreturns the time as an eight-byte ASCII character string of the form:hh:mm:ssFor example:16:45:23Note that a 24-hour clock is used.PGI Fortran Reference Guide 215