text: #ifndef _SYSCALL_H_
  #define _SYSCALL_H_
  
  // System call numbers
  #define SYS_fork       1
  #define SYS_exit       2
  #define SYS_wait       3
  #define SYS_pipe       4
  #define SYS_write      5
  #define SYS_read       6
  #define SYS_close      7
  #define SYS_kill       8
  #define SYS_exec       9
  #define SYS_open      10
  #define SYS_mknod     11
  #define SYS_unlink    12
  #define SYS_fstat     13
  #define SYS_link      14
  #define SYS_mkdir     15
  #define SYS_chdir     16
  #define SYS_dup       17
  #define SYS_getpid    18
  #define SYS_sbrk      19
  #define SYS_sleep     20
  #define SYS_uptime    21
  #define SYS_setticket 22
  #define SYS_getticket 23
  #define SYS_getpinfo  24
  #define SYS_clone     25
  #define SYS_join      26
  #endif // _SYSCALL_H_
  