Name

utc_addtime - Computes the sum of two binary timestamps

Synopsis

#include <dce/utc.h> int utc_addtime(
utc_t∗ result,
utc_t ∗utc1,
utc_t ∗utc2);

Parameters

Input

utc1Binary timestamp or relative binary timestamp.  Use NULL if you want this routine to use the current time for this parameter. 

utc2Binary timestamp or relative binary timestamp.  Use NULL if you want this routine to use the current time for this parameter. 

Output

resultResulting binary timestamp or relative binary timestamp, depending upon the operation performed:

       •relative time+relative time=relative time

       •absolute time+relative time=absolute time

       •relative time+absolute time=absolute time

       •absolute time+absolute time is undefined.  (See the note later in this reference page.) 

Description

The utc_addtime() routine adds two binary timestamps, producing a third binary timestamp whose inaccuracy is the sum of the two input inaccuracies.  One or both of the input timestamps typically represents a relative (delta) time.  The TDF in the first input timestamp is copied to the output.  The timestamps can be two relative times or a relative time and an absolute time. 

Notes

Although no error is returned, the combination absolute time+absolute time should not be used. 

Return Values

 0Indicates that the routine executed successfully. 

-1Indicates an invalid time parameter or invalid results. 

Examples

The following example shows how to compute a timestamp that represents a time at least 5 seconds in the future. 

utc_t               now, future, fivesec;
reltimespec_t       tfivesec;
timespec_t          tzero;
 /∗   Construct a timestamp that represents 5 seconds...
 ∗/
tfivesec.tv_sec = 5;
tfivesec.tv_nsec = 0;
tzero.tv_sec = 0;
tzero.tv_nsec = 0;
utc_mkbinreltime(&fivesec,    /∗ Out: 5 secs in binary timestamp    ∗/
                 &tfivesec,   /∗ In:  5 secs in timespec            ∗/
                 &tzero);     /∗ In:  0 secs inaccuracy in timespec ∗/
 /∗    Get the maximum possible current time...
 ∗    (The NULL input parameter is used to specify the current time.)
 ∗/
utc_pointtime((utc_t ∗)0,     /∗ Out: Earliest possible current time ∗/
              (utc_t ∗)0,     /∗ Out: Midpoint of current time       ∗/
              &now,           /∗ Out: Latest possible current time   ∗/
              (utc_t ∗)0);    /∗ In:  Use current time               ∗/
 /∗   Add 5 seconds to get future timestamp...
 ∗/
utc_addtime(&future,          /∗ Out: Future binary timestamp      ∗/
            &now,             /∗ In:  Latest possible time now     ∗/
            &fivesec);        /∗ In:  5 secs                       ∗/

Related Information

Functions: utc_subtime(3dts).