timespec

struct timeval represents and instant in time with two members, tv_sec (seconds) and tv_usec (microseconds). In this representation, tv_usec is not by itself an absolute time it is a sub second offset off of tv_sec . struct timespec works the same way except that instead of microseconds it's offset ( tv_nsec ) is stored in nanosecond units. The question is: Is there a standard way to convert between these two? Looking at this doc , I would think multiplying tv_usec by 1000 is sufficient to get tv_nsec . More important, I suspect is the source of the different structures: they could be filled

On posix it is possible to use timespec to calculate accurate time length (like seconds and milliseconds). Unfortunately I need to migrate to windows with Visual Studio compiler. The VS time.h library doesn't declare timespec so I'm looking for other options. As far as could search is it possible to use clock and time_t although I could't check how precise is counting millisecons with clock counting. What do you do/use for calculating time elapse in a operation (if possible using standards c++ library) ? Grim The function GetTickCount is usually used for that. Also a similiar thread: C++

This question already has an answer here: Timespec :struct type Error c2011 4 answers While executing a Pthread program in C using Visual Studio 2015, I got the following error: Error C2011 'timespec': 'struct' type redefinition The following is my code: #include<pthread.h> #include<stdlib.h> #include<stdio.h> void *calculator(void *parameter); int main(/*int *argc,char *argv[]*/) { pthread_t thread_obj; pthread_attr_t thread_attr; char *First_string = "abc"/*argv[1]*/; pthread_attr_init(&thread_attr); pthread_create(&thread_obj,&thread_attr,calculator,First_string); } void *calculator(void

When I try to compile this on Linux with gcc -std=c99 , the compiler complains about not knowing struct timespec . However if I compile this without -std=c99 everything works fine. #include <time.h> int main(void) { struct timespec asdf; return 0; } Why is this and is there a way to still get it to work with -std=c99 ? Explicitly enabling POSIX features The timespec comes from POSIX, so you have to 'enable' POSIX definitions: #if __STDC_VERSION__ >= 199901L #define _XOPEN_SOURCE 600 #else #define _XOPEN_SOURCE 500 #endif /* __STDC_VERSION__ */ #include <time.h> void blah(struct timespec asdf)