.TH CHMOD 1 sbase\-VERSION
.SH NAME
chmod \- change file mode
.SH SYNOPSIS
.B chmod
.RB [ \-r ]
.I octal
.RI [ file ...]
.P
.B chmod
.RB [ \-r ]
.RB [ ugoa ]*[ +-= ][ rwxs ]*
.RI [ file ...]
.SH DESCRIPTION
.B chmod
changes the file mode for the given files.
.P
If the mode is an
.I octal
number, the modes are set according to that number's comprising bits. The first
digit defines the setuid (4) and setgid (2) attributes.  The second digit
defines the owner's permissions: read (4), write (2), and execute (1); the third
defines permissions for others in the file's group; and the fourth for all other
users. Leading zeroes may be omitted.
.P
Alternatively the mode may be symbolic. The symbol meanings are:
.TP
.B u
modifies owner permissions.
.PD 0
.TP
.B g
modifies group permissions.
.TP
.B o
modifies other user permissions.
.TP
.B a
modifies all user permissions.
.PD
.TP
.B +
adds the given permissions to the mode.
.PD 0
.TP
.B -
removes the given permissions from the mode.
.TP
.B =
sets the mode to the given permissions.
.PD
.TP
.B r
read permissions.
.PD 0
.TP
.B w
write permissions.
.TP
.B x
execute permissions.
.TP
.B s
setuid and setgid attributes.
.PD
.SH OPTIONS
.TP
.B \-r
change directory mode recursively.
.SH SEE ALSO
.IR chmod (2)