[nptl-intel] question about clock_settime() and CLOCK_REALTIME

[Li, Adam]

Hi all,
 
I ran a simple test case for clock_settime() using CLOCK_REALTIME on linux-2.6.1 kernel and libc-2004-02-01. But clock_settime()
failed with EINVAL. It seems there is some configuration problem when I build libc. The clock_settime() system will not be invloked
although I am running on 2.6.1 kernel. But I cannot found out what is the problem.
 
 
Platform:
--------------------
libc: 2004-02-01
Linux kernel: 2.6.1-mm2 SMP on ia32
gcc-3.3.3-20040209
Redhat EL-3.0-update1
 
My configurations:
------------------------
configure --prefix=/usr  --enable-add-ons=nptl --with-tls  --with-headers=/usr/src/linux-2.6.1/include --enable-kernel=2.6.0
 
Output:
-------------------
clock_gettime(): Success
clock_settime(): Invalid argument
clock_settime() failed
 
 
Thanks 
 
-adam
 
 
test cases: (adapted from Posix Test project: conformance/interfaces/clock_settime/1-1.c)
--------------------------
#include <stdio.h>
#include <time.h>
#include <unistd.h>
#include <errno.h>
 
int main(int argc, char *argv[])
{
        struct timespec tpset;
 
        clock_gettime(CLOCK_REALTIME, &tpset);
        perror("clock_gettime()");
        tpset.tv_sec++;
        if (clock_settime(CLOCK_REALTIME, &tpset) == 0) {
                printf("Test PASSED\n");
                return 0;
        }
        perror("clock_settime()");
        printf("clock_settime() failed\n");
        return -1;
}
 
strace shows that clock_settime() did not invoke system call. libc returns EINVAL:
...........
clock_gettime(0, {1077213432, 77164000}) = 0
dup(2)                                  = 3
fcntl64(3, F_GETFL)                     = 0x8002 (flags O_RDWR|O_LARGEFILE)
brk(0)                                  = 0x804a000
brk(0x806b000)                          = 0x806b000
brk(0)                                  = 0x806b000
fstat64(3, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 3), ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x40018000
_llseek(3, 0, 0xbfffefb8, SEEK_CUR)     = -1 ESPIPE (Illegal seek)
write(3, "clock_gettime(): Success\n", 25clock_gettime(): Success
) = 25
close(3)                                = 0
munmap(0x40018000, 4096)                = 0
dup(2)                                  = 3
fcntl64(3, F_GETFL)                     = 0x8002 (flags O_RDWR|O_LARGEFILE)
fstat64(3, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 3), ...}) = 0
mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 0x40018000
_llseek(3, 0, 0xbfffefb8, SEEK_CUR)     = -1 ESPIPE (Illegal seek)
write(3, "clock_settime(): Invalid argumen"..., 34clock_settime(): Invalid argument
) = 34
close(3)
.........................
   
------------------------------------------------
Message above is personal view, not my employer's.