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