open <filename> [flag | mode]

[root@sylixos:/root]# help open           
open a file.
filename : file name
flag : O_RDONLY   : 00000000
       O_WRONLY   : 00000001
       O_RDWR     : 00000002
       O_APPEND   : 00000008
       O_SHLOCK   : 00000010
       O_EXLOCK   : 00000080
       O_ASYNC    : 00000040
       O_CREAT    : 00000200
       O_TRUNC    : 00000400
       O_EXCL     : 00000800
       O_SYNC     : 00002000
       O_NONBLOCK : 00004000
       O_NOCTTY   : 00008000
       O_CLOEXEC  : 00080000
mode : create file mode, eg: 0666
open [filename flag mode]
[root@sylixos:/root]# 

[root@sylixos:/apps/test]# ls
hello.c
[root@sylixos:/apps/test]# open hello.c 2
open file return: 8 dev 170000 inode 37c8 size 18
[root@sylixos:/apps/test]# files
kernel filedes show (process filedes in /proc/${pid}/filedes) >>
 fd abn name                       type   drv
  3     /dev/console               orig    19 GLB STD_IN GLB STD_OUT GLB STD_ERR
  4     /dev/socket                socket  33
  5     /dev/socket                socket  33
  6     /dev/ttyS0                 orig    19
  7     /dev/input/xkbd            new_1   37
  8     /apps/test/hello.c         new_1   23
  9     /dev/hotplug               orig    12
[root@sylixos:/apps/test]# ls
hello.c
[root@sylixos:/apps/test]# open temp.txt 0666
open file return: 10 dev 170000 inode 37da size 0
[root@sylixos:/apps/test]# ls
hello.c  temp.txt
[root@sylixos:/apps/test]# files
kernel filedes show (process filedes in /proc/${pid}/filedes) >>
 fd abn name                       type   drv
  3     /dev/console               orig    19 GLB STD_IN GLB STD_OUT GLB STD_ERR
  4     /dev/socket                socket  33
  5     /dev/socket                socket  33
  6     /dev/ttyS0                 orig    19
  7     /dev/input/xkbd            new_1   37
  8     /apps/test/hello.c         new_1   23
  9     /dev/hotplug               orig    12
 10     /apps/test/temp.txt        new_1   23
[root@sylixos:/apps/test]#