+ X/Open defines no error conditions. In this implementa-
+ tion
+
+ <STRONG>def_prog_mode</STRONG>, <STRONG>def_shell_mode</STRONG>, <STRONG>reset_prog_mode</STRONG>, <STRONG>re-</STRONG>
+ <STRONG>set_shell_mode</STRONG>
+ return an error if the terminal was not ini-
+ tialized, or if the I/O call to obtain the
+ terminal settings fails.
+
+ <STRONG>ripoffline</STRONG>
+ returns an error if the maximum number of
+ ripped-off lines exceeds the maximum (NRIPS =
+ 5).
+