Hi,
I added a temporary system call in the kernel for a test,
But when a program calls the system call, an error occurs.
When I compiled the following program, an error occured.
# vi testcall_test.c
Code:
#include <linux/unistd.h>
_syscall0(int,testcall);
int main(void)
{
testcall();
return 0;
}
The error messages are...
# gcc -I /usr/src/linux-2.6.14.6/include testcall_test.c -o testcall_test
Code:
/usr/bin/ld: errno: TLS definition in /lib/libc.so.6 section .tbss mismatches non-TLS reference in /tmp/ccCGdJnX.o
/lib/libc.so.6: could not read symbols: Bad value
collect2: ld returned 1 exit status
But when the program calls the system call as the number,
it works properly.
WHAT IS WRONG WITH THE ABOVE?
And how can I solve the problem?
Please, help me.
# vi testcall_test.c
Code:
#include <linux/unistd.h>
// _syscall0(int,testcall);
int main(void)
{
// testcall();
syscall(294);
return 0;
}
(or)
# vi testcall_test.c
Code:
#include <linux/unistd.h>
// _syscall0(int,testcall);
int main(void)
{
// testcall();
syscall(__NR_testcall);
return 0;
}
# gcc -I /usr/src/linux-2.6.14.6/include testcall_test.c -o testcall_test
#
# ls
testcall_test testcall_test.c
# ./testcall_test
testcall success!
#
I heard that the _syscallN() macros are gone in 2.6.20 and later.
But the current kernel version is 2.6.14.6
