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diff --git a/man/chmod.x b/man/chmod.x new file mode 100644 index 000000000..f8051fd89 --- /dev/null +++ b/man/chmod.x @@ -0,0 +1,55 @@ +[DESCRIPTION] +This manual page +documents the GNU version of +.BR chmod . +.B chmod +changes the permissions of each given file according to +.IR mode , +which can be either a symbolic representation of changes to make, or +an octal number representing the bit pattern for the new permissions. +.PP +The format of a symbolic mode is +`[ugoa...][[+-=][rwxXstugo...]...][,...]'. Multiple symbolic +operations can be given, separated by commas. +.PP +A combination of the letters `ugoa' controls which users' access to +the file will be changed: the user who owns it (u), other users in the +file's group (g), other users not in the file's group (o), or all +users (a). If none of these are given, the effect is as if `a' were +given, but bits that are set in the umask are not affected. +.PP +The operator `+' causes the permissions selected to be added to the +existing permissions of each file; `-' causes them to be removed; and +`=' causes them to be the only permissions that the file has. +.PP +The letters `rwxXstugo' select the new permissions for the affected +users: read (r), write (w), execute (or access for directories) (x), +execute only if the file is a directory or already has execute +permission for some user (X), set user or group ID on execution (s), +save program text on swap device (t), the permissions that the user +who owns the file currently has for it (u), the permissions that other +users in the file's group have for it (g), and the permissions that +other users not in the file's group have for it (o). +.PP +A numeric mode is from one to four octal digits (0-7), derived by +adding up the bits with values 4, 2, and 1. Any omitted digits are +assumed to be leading zeros. The first digit selects the set user ID +(4) and set group ID (2) and save text image (1) attributes. The +second digit selects permissions for the user who owns the file: read +(4), write (2), and execute (1); the third selects permissions for +other users in the file's group, with the same values; and the fourth +for other users not in the file's group, with the same values. +.PP +.B chmod +never changes the permissions of symbolic links; the +.B chmod +system call cannot change their permissions. This is not a problem +since the permissions of symbolic links are never used. +However, for each symbolic link listed on the command line, +.B chmod +changes the permissions of the pointed-to file. +In contrast, +.B chmod +ignores symbolic links encountered during recursive directory +traversals. +.SH OPTIONS |