How can I use syscall() from 32-bit application in 64-bit Solaris (v. 5.8)

Hello again.

You may use the debugger (mdb) to open the core file generated by the SIGSYS trap:mdb core

Then you type::regs

to list the register values at the time of the trap (in hexadecimal form).

For Sparc machines (it is more complicated on x86 machines) g1 holds the system call number, o0 holds the first argument, o1 the second one ... o5 the 6th one. (For system calls with more than 6 arguments the 7th, 8th... argument are stored on the stack.)

If g1 is 0 you know that the system call is done indirectly using SYS_syscall so the arguments are shifted (see above) and o0 holds the system call number.

You can exit mdb using::quit

Martin

Martin_Rosenaua at 2007-7-12 19:21:26 >

Your loadable module (not your application) must be written in a way to support both 32 and 64 bit applications in this case. Looking at OpenSolaris's file "uts/common/syscall/pipe.c" I think the following code should work:

static struct modlsys modlsys = {

&mod_syscallops, "My system call", &my_system_call

};

#ifdef KERNEL_IS_64_BITS

static struct modlsys modlsys32 = {

&mod_syscallops32, "My system call (app is 32 bits)", &my_system_call

};

#endif

static struct modlinkage modlinkage = {

MODREV_1,

&modlsys,

#ifdef KERNEL_IS_64_BITS

&modlsys32,

#endif

NULL

};

Martin

Martin_Rosenaua at 2007-7-12 19:21:26 >

... but when I add to my kernel module necessary code:

#ifdef _SYSCALL32_IMPL

static struct modlsys modlsys32 =

{

&mod_syscallops32,

"modify_bits 32-bit",/* module name */

&mysysent

};

#endif

I see that they are not compiled, because symbol _SYSCALL32_IMPL is not defined.

How to compile this code properly (with_SYSCALL32_IMPL definition)?

Dear_Serga at 2007-7-12 19:21:26 >