/*
* (c) The GRASP/AQUA Project, Glasgow University, 1994-1998
*
- * $Id: getClockTime.c,v 1.6 1999/09/30 12:38:44 sof Exp $
+ * $Id: getClockTime.c,v 1.7 1999/10/20 10:08:33 sof Exp $
*
* getClockTime Runtime Support
*/
#include "Rts.h"
#include "stgio.h"
-/* It seems morally wrong to skew this in favour of
- using non-POSIX calls (gettimeofday(), ftime()..),
- rather than time()....so, let's re-order it all
- (and hope OS idiosyncracies won't get in the way
- of using time(), the moral elite's favourite.)
+/* Note: skewing this code in favour of non-POSIX calls
+ such as gettimeofday() and getclock() rather than time(),
+ may seem strange/wrong. There's a good reason for it
+ though - the non-POSIX calls gives you better precision --
+ they return usecs (or nsecs) as well as seconds, which
+ the users of getClockTime() is interested in knowing.
*/
-#if defined(HAVE_TIME_H)
-# include <time.h>
+#if defined(HAVE_GETTIMEOFDAY)
+# ifdef HAVE_SYS_TIME_H
+# include <sys/time.h>
+# endif
#elif defined(HAVE_GETCLOCK)
# ifdef HAVE_SYS_TIMERS_H
# define POSIX_4D9 1
# include <sys/timers.h>
# endif
-#elif defined(HAVE_GETTIMEOFDAY)
-# ifdef HAVE_SYS_TIME_H
-# include <sys/time.h>
-# endif
+#elif defined(HAVE_TIME_H)
+# include <time.h>
#endif
#ifdef HAVE_WINDOWS_H
((unsigned int *)sec)[0] = (unsigned int)t.time;
((unsigned int *)nsec)[0] = (unsigned int)t.millitm * 1000;
return 0;
-#elif defined(HAVE_TIME_H)
- time_t t;
- if ((t = time(NULL)) == (time_t) -1) {
+#elif defined(HAVE_GETTIMEOFDAY)
+ struct timeval tp;
+
+ if (gettimeofday(&tp, NULL) != 0) {
cvtErrno();
stdErrno();
return -1;
}
- ((unsigned long int *)sec)[0] = t;
- ((unsigned long int *)nsec)[0] = 0;
+ ((unsigned long int *)sec)[0] = tp.tv_sec;
+ ((unsigned long int *)nsec)[0] = tp.tv_usec * 1000;
return 0;
#elif defined(HAVE_GETCLOCK)
struct timespec tp;
((unsigned long int *)sec)[0] = tp.tv_sec;
((unsigned long int *)nsec)[0] = tp.tv_nsec;
return 0;
-#elif defined(HAVE_GETTIMEOFDAY)
- struct timeval tp;
-
- if (gettimeofday(&tp, NULL) != 0) {
+#elif defined(HAVE_TIME_H)
+ time_t t;
+ if ((t = time(NULL)) == (time_t) -1) {
cvtErrno();
stdErrno();
return -1;
}
- ((unsigned long int *)sec)[0] = tp.tv_sec;
- ((unsigned long int *)nsec)[0] = tp.tv_usec * 1000;
+ ((unsigned long int *)sec)[0] = t;
+ ((unsigned long int *)nsec)[0] = 0;
return 0;
#else
#error "getClockTime: don't know how to get at the clock's time"