SYSCALL_GET_NR(9) Machine State SYSCALL_GET_NR(9)NAMEsyscall_get_nr - find what system call a task is executing
SYNOPSIS
int syscall_get_nr(struct task_struct * task, struct pt_regs * regs);
ARGUMENTS
task
task of interest, must be blocked
regs
task_pt_regs of task
DESCRIPTION
If task is executing a system call or is at system call tracing about
to attempt one, returns the system call number. If task is not
executing a system call, i.e. it´s blocked inside the kernel for a
fault or signal, returns -1.
Note this returns int even on 64-bit machines. Only 32 bits of system
call number can be meaningful. If the actual arch value is 64 bits,
this truncates to 32 bits so 0xffffffff means -1.
It´s only valid to call this when task is known to be blocked.
Kernel Hackers Manual 2.6. November 2013 SYSCALL_GET_NR(9)