11.11 Time stamp

Purpose:

To provide a time stamp, which records (with the accuracy of 1 second) the time and date, when the object was created or modified.

In C++, the time stamp is not automatically initialized when creating a new object, unless you place macro ZZ_INIT() or call function setTime() in all constructors. For example:

class myObj { // first variantD
    int i,k;
    ZZ_EXT_myObj
public:
    myObj(){this->setID();}
    myObj(int ii, int kk){this->setID("myObj",1); i=ii; k=kk;}
};
ZZ_HYPER_TIME_STAMP(myObj);
class myObj { // second variant, covers two initializations
    int i,k;
    ZZ_EXT_myObj
public:
    myObj(){ZZ_INIT(myObj);}
    myObj(int ii, int kk){ZZ_INIT(myObj); i=ii; k=kk;}
};
ZZ_HYPER_TIME_STAMP(myObj);
ZZ_HYPER_SELF_ID(myObj);

TIME_STAMP is one of the special hard-wired organizations that can have only one instance on any given object. Though it is declared as

ZZ_HYPER_TIME_STAMP(objType);

it does not create a hyper object. Functions manipulating this organization are associated with the object itself, and not with a general id.

Internally, the stamp is packed into 4 bytes. For a convenient comparison of two time stamps, the special function cmpTime() is available.

getTime() returns the time stamp unpacked in 6 bytes, each representing one number (year, month, day, hour, minute, second).

Note that the time stamp is kept only on specified object types (those for which ZZ_HYPER_TIME_STAMP() have been declared).

Syntax:

// TYPE is the type of the given object
ZZ_HYPER_TIME_STAMP(TYPE);
char ts[6];
void TYPE::setTime(void); 		sets the time stamp on the given object to the current time.
void TYPE::getTime(ts); returns time stamp of the given object [YMDHMS] in ts. For example, June 18, 1989 17:30:11 is represented as [89 6 18 17 30 11].
int TYPE::cmpTime(TYPE *obj2); compares two objects and returns int i<0 when obj1 is older, i=0 when both objects have the same age, i>0 when obj2 is older. Example of use: i=obj1->cmpTime(obj2).

You don't have to worry about the year 2000 and up. The time stamp can be set only to the current date.

Examples:

  1. test4d.c

 

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