hi ... i am completely stuck with this ...i am working on a C (and only C) project in which i have to handle the dates till the resolution of milliseconds.. the problem is that using the current ANSI/C89 standard functions i can only get the time till the resolution of seconds... eg: i want the time to be displayed like 10:12:23:11 but with the set of functions available i can only get the time as 10:12:23 there are few functions like _ftime(windows) and gettimeofday(linux) which gives the answer i desire but these functions do not conform to the ANSI/C89 standard.hence i cannot use them. expecting a quick help from all of u out there :goofy:
there must be some way through which i can straight away get the time from the system... may be using some assembly.. and i am sure that system do returns the time with a millisecond resolution ..that is why function like ftime works..
For sure there IS a way if you resort to IMPLEMENTATION SPECIFIC approaches. But you're also saying that it also has to be ANSI-C89, and there is no standard function which is guaranteed to be available on all systems. The question is, do you want to relax your C89 only requirement and use a platform specific API or not?
what i am looking for must work both on windows and linux..and should conform to ANSI-C89 standard.. 1) there are interpreters called spidermonkey (used by Mozilla) and SEE ...these guys have implemented this thing using C and conforming to standards...even though the source is OPEN i am not able to make out how they have done it .. :worried: the interpreters are for JavaScript and they have done the above asked things to implementing Date object for javaScript 2) is there any way i can know how these standard C function (time()) get the system time ..i might be able to do something in that case...because what i know is that the system returns a value with a sub second resolution and this function discards the value and only use the value till the seconds resolution..
They do it by having something like Code: #ifdef WIN32 int myTime ( void ) { int result = ftime(); // or whatever return result; } #elif POSIX int myTime ( void ) { int result = gettimeofday(); // or whatever return result; } #else #error bad platform for myTime #endif Except there are better ways of doing it, but that's the idea. You wrap the implementation specific parts of the code up in a consistent internal API call (in this case, myTime() ), which you can call from the rest of your ANSI-C89 code. > even though the source is OPEN i am not able to make out how they have done it Dig deeper, and look for the platform specific API calls. They will be there somewhere for sure.
thanks a ton for the help ... i looked into the OPEN source again and this time i have found that they have done a platform specific implementation ... the problem is that i have to follow the standard calls because i dont know in which platform the final application will be run ..!! so if i continue with the ifdef [\B] way ..i have to consider quite a lot of platoforms before i am assured that my application will run smoothly.. thanks again for the help..
> because i dont know in which platform the final application will be run And neither do the applications you've looked at. You don't just "run" a C program on a machine, you have to compile it first (or 'make' in larger programs). This act of creating a runnable program is where the choice of actual implementation takes place. > i have to consider quite a lot of platoforms before i am assured that my application will run smoothly.. That's the way it is. Grab any portable library (say http://www.zlib.net/) and you'll see all sorts of portability hackery.
>> And neither do the applications you've looked at. I completely agree >>You don't just "run" a C program on a machine, you have to compile it first (or 'make' in larger programs). This act of creating a runnable program is where the choice of actual implementation takes place. I know this and by run i mean the platform on which the application with its library will be compiled and then run >>That's the way it is. Grab any portable library (say http://www.zlib.net/) and you'll see all sorts of portability hackery. Thanks ..I will definitely look into it..
