syscalls_study with inline assembly for i386, x86-64, x32

1. examples of legacy syscall int $0x80:

   • legacy_syscall_exit_with_sw_irq.c
   • legacy_syscall_fork_with_sw_irq.c

2. examples of 32-bit fast syscalls (__kernel_vsyscall, sysenter/sysexit)

   • fast_syscall32_exit_sysenter.c gcc -m32 -o exit_sysenter fast_syscall32_exit_sysenter.c

   • fast_syscall32_chdir_sysenter.c gcc -m32 -o chdir_sysenter fast_syscall32_chdir_sysenter.c

3. examples of 64-bit fast syscalls (syscall/sysret)

   • fast_syscall64_exit_syscall.c
   • fast_syscall64_fork_syscall.c

4. examples of glibc syscall wrapper usage (may be clone3 case)

   • glibc_syscall_wrapper_exit.c
   • glibc_syscall_wrapper_uname.c

5. not_work, more examples for fast 64-bit syscalls to play later.