Timespec redefinition error
c, pthreads, timespec, visual-studio, windows
Solution
pthreads-win32 (which I assume you're using) may internally include `time.h` (`time.h` is also commonly included by other libraries/headers) - and `time.h` already declares `timespec` (also, it does so in a way compatible with pthreads) - yet the pthreads-win32's `pthread.h` doesn't have the valid include guards for this case (shame on them!). pthreads tries to declare it because it needs it internally, but since it's possible it won't need the entire `time.h`, it tries to declare only the `timespec` if possible. Still, you can simply add
#define HAVE_STRUCT_TIMESPEC
before `#include <pthread.h>` - that will tell the pthreads-win32 header that you already have a proper `timespec`, and will let your code compile properly.
Alternatively, if you're using pthreads extensively, you may wish to edit the header file itself - simply add that `#define HAVE_STRUCT_TIMESPEC` to it somewhere near the beginning, and you're good to go.
Further reading: http://mingw-users.1079350.n2.nabble.com/mingw-error-redefinition-of-struct-timespec-td7583722.html
Problem
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 *parameter) { int x=atoi((char*)parameter); printf("x=%d", x); } ``` The `pthread.h` header file contains the following code related to timespec: ``` #if !defined(HAVE_STRUCT_TIMESPEC) #define HAVE_STRUCT_TIMESPEC #if !defined(_TIMESPEC_DEFINED) #define _TIMESPEC_DEFINED struct timespec { time_t tv_sec; long tv_nsec; }; #endif /* _TIMESPEC_DEFINED */ #endif /* HAVE_STRUCT_TIMESPEC */ ``` No other header file which I use uses the `timespec` struct, so there is no chance of redefining. There is no chance of a corrupted header file because it has been downloaded from pthread opensource website.