fix typos

us.1

@@ -35,7 +35,7 @@ calling user's username.
 .PP
 Invoking the program logs by default to
 .BR syslog(2)
-the outcome of the invocation, this behaviour can be changed in the config.
+the outcome of the invocation, this behavior can be changed in the config.
 
 .SH OPTIONS
 .IP \-h
@@ -65,9 +65,8 @@ Use the specified config file
 .SH "RETURN VALUE"
 The
 .BR us
-utility returns 0 on success and != 0 on failure which may occur on
-various occasions, along with an error a message will be outputted to specify
-the reason.
+utility returns 0 on success and != 0 on failure which may occur on various
+occasions. An error message will be outputted to specify the reason.
 
 .SH "SEE ALSO"
 .BR su(1)

us.conf.5

@@ -51,7 +51,7 @@ execution of the command. A valid environment variable list starts with an
 uppercase letter and ends at the next space.
 .PP
 A valid config line must be owned by root:root and should not be readable,
-writeable or executable for any other user or group, if the config file fails
+writable or executable for any other user or group, if the config file fails
 to meet this requirements it will get rejected and invocation will fail.
 
 .SH FILES
@@ -90,6 +90,11 @@ the group 'coolppl' because joe is uncool
 - joe as :coolppl
 .EE
 
+.SH LIMITATIONS
+.PP
+Due to the way the environment is parsed, neither the name nor the value can
+contain commas.
+
 .SH "SEE ALSO"
 .BR us(1)