Added public files
Roughly added all public files. Probably missed some, though.
diff --git a/doc/master/valid_read b/doc/master/valid_read
new file mode 100644
index 0000000..2dafbae
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+++ b/doc/master/valid_read
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+SYNOPSIS
+ string valid_read(string path, string uid, string func, object ob)
+
+DESCRIPTION
+ This function is called to check if the object ob with the
+ user-id uid has read permissions for the file given by path
+ for the operation named by func. It should return 0 if
+ permission is denied, or the normalized path if permission is
+ granted. You can also return 1 to indicate that the path can
+ be used unchanged.
+
+ The returned pathname must not contain ``..'', a leading /
+ will be stripped by the interpreter.
+
+ Func denotes the efun call or other operation that caused
+ valid_read() to be called:
+ ed_start (check if the file to be edited is readable),
+ file_size,
+ get_dir,
+ print_file (efun cat()),
+ read_bytes,
+ read_file,
+ restore_object,
+ tail.
+
+ Note that this function is called in compat mode as well. If
+ you need to be compatible with the old 2.4.5-mudlib, redirect
+ these calls to the valid_read/valid_write in the user
+ object.
+
+SEE ALSO
+ valid_write(M), make_path_absolute(M)