[GRASS5] R_get_location_with_* and nanosleep

[Radim Blazek]

Just a dead end. I tried again to add nanosleep to R_get_location_with_* 
  functions:

configure.in:
have_nanosleep=false
NANOSLEEPLIB=
AC_CHECK_FUNC(nanosleep, have_nanosleep=true , [
AC_CHECK_LIB(nanoslee, rt, NANOSLEEPLIB=-lrt have_nanosleep=true, [
AC_CHECK_LIB(nanosleep, posix4, NANOSLEEPLIB=-lposix4 have_nanosleep=true, [
     AC_MSG_WARN([*** Unable to locate nanosleep() function.])
])])])
AC_SUBST(NANOSLEEPLIB)

if ${have_nanosleep}; then
     AC_DEFINE(HAVE_NANOSLEEP)
fi

R_get_location_with_*:
#ifdef HAVE_NANOSLEEP
             {
                 struct timespec req;
                 int ret;
                 req.tv_sec=0;
                 req.tv_nsec=1000000;
                 ret = nanosleep(&req,NULL);
             }
#endif

It does not work, it is too slow, I dont know why, man page:

   | The current implementation of nanosleep is based on the normal
   | kernel timer mechanism, which has a resolution  of  1/HZ s
   | (i.e,  10 ms  on | Linux/i386 and 1 ms on Linux/Alpha).

which should be enough.

Radim