Linux下系统调用的小知识

Linux下有哪些系统调用,在哪里可以查到

在/usr/include/asm/unistd.h

具体内容如代码所示

/* File autogenerated by 'make headers_install' */
#ifndef __ASM_STUB_UNISTD_H
#define __ASM_STUB_UNISTD_H
# if defined __x86_64__
#  include <asm-x86_64/unistd.h>
# elif defined __i386__
#  include <asm-i386/unistd.h>
# else
#  warning This machine appears to be neither x86_64 nor i386.
# endif
#endif /* __ASM_STUB_UNISTD_H */
~

我的机器是x86_64 位系统，内容为

ifndef _ASM_X86_64_UNISTD_H_
#define _ASM_X86_64_UNISTD_H_

#ifndef __SYSCALL
#define __SYSCALL(a,b)
#endif

/*
 * This file contains the system call numbers.
 *
 * Note: holes are not allowed.
 */

/* at least 8 syscall per cacheline */
#define __NR_read                                0
__SYSCALL(__NR_read, sys_read)
#define __NR_write                               1
__SYSCALL(__NR_write, sys_write)
#define __NR_open                                2
__SYSCALL(__NR_open, sys_open)
#define __NR_close                               3
__SYSCALL(__NR_close, sys_close)
#define __NR_stat                                4
__SYSCALL(__NR_stat, sys_newstat)
#define __NR_fstat                               5
__SYSCALL(__NR_fstat, sys_newfstat)
#define __NR_lstat                               6
__SYSCALL(__NR_lstat, sys_newlstat)
#define __NR_poll                                7
__SYSCALL(__NR_poll, sys_poll)

#define __NR_lseek                               8
__SYSCALL(__NR_lseek, sys_lseek)
#define __NR_mmap                                9
__SYSCALL(__NR_mmap, sys_mmap)
#define __NR_mprotect                           10
__SYSCALL(__NR_mprotect, sys_mprotect)
#define __NR_munmap                             11
__SYSCALL(__NR_munmap, sys_munmap)
#define __NR_brk                                12
__SYSCALL(__NR_brk, sys_brk)
#define __NR_rt_sigaction                       13
__SYSCALL(__NR_rt_sigaction, sys_rt_sigaction)
#define __NR_rt_sigprocmask                     14
__SYSCALL(__NR_rt_sigprocmask, sys_rt_sigprocmask)
#define __NR_rt_sigreturn                       15
__SYSCALL(__NR_rt_sigreturn, stub_rt_sigreturn)