4BSD/usr/man/cat2/chmod.2

Compare this file to the similar file:
Show the results in this format:



CHMOD(2)            UNIX Programmer's Manual             CHMOD(2)



NAME
     chmod - change mode of file

SYNOPSIS
     chmod(name, mode)
     char *name;

DESCRIPTION
     The file whose name is given as the null-terminated string
     pointed to by _n_a_m_e has its mode changed to _m_o_d_e.  Modes are
     constructed by _o_ring together some combination of the fol-
     lowing:

           04000 set user ID on execution
           02000 set group ID on execution
           01000 save text image after execution
           00400 read by owner
           00200 write by owner
           00100 execute (search on directory) by owner
           00070 read, write, execute (search) by group
           00007 read, write, execute (search) by others

     If an executable file is set up for sharing (this is the
     default) then mode 1000 prevents the system from abandoning
     the swap-space image of the program-text portion of the file
     when its last user terminates.  Ability to set this bit is
     restricted to the super-user since swap space is consumed by
     the images.  See _s_t_i_c_k_y(8).

     Only the owner of a file (or the super-user) may change the
     mode.  Only the super-user can set the 1000 mode.

     On some systems, writing or changing the owner of a file
     turns off the set-user-id bit.  This makes the system some-
     what more secure by protecting set-user-id files from
     remaining set-user-id if they are modified, at the expense
     of a degree of compatibility.

SEE ALSO
     chmod(1)

DIAGNOSTIC
     Zero is returned if the mode is changed; -1 is returned if
     _n_a_m_e cannot be found or if current user is neither the owner
     of the file nor the super-user.

ASSEMBLER (PDP-11)
     (chmod = 15.)
     sys chmod; name; mode






Printed 11/10/80                                                1