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about time and time_t

Hello everyone,
In MSDN for time function,

time_t time(
time_t *timer
);

http://msdn2.microsoft.com/en-us/lib...33(VS.80).aspx

the return value of time is time_t, but in the Return Value section, it
mentioned,

Return the time as seconds elapsed since midnight, January 1, 1970. There is
no error return.

So, I am wondering whether time_t could be represented as elapsed number of
seconds correctly and safely -- no data lost if we convert return value to
unsigned long?

Like,

unsigned long second = time (NULL);
thanks in advance,
George
Oct 29 '07 #1
1 1235
>In MSDN for time function,
>
time_t time(
time_t *timer
);

http://msdn2.microsoft.com/en-us/lib...33(VS.80).aspx

the return value of time is time_t, but in the Return Value section, it
mentioned,

Return the time as seconds elapsed since midnight, January 1, 1970. There is
no error return.

So, I am wondering whether time_t could be represented as elapsed number of
seconds correctly and safely -- no data lost if we convert return value to
unsigned long?
George,

time_t is (in later compilers) defined as a 64-bit value (with the
option of being a 32-bit value for backward compatibility). It's best
if you play by the rules and use it with appropriate functions such as
difftime.

Dave
Oct 29 '07 #2

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