=head1 NAME
-ERR_error_string - obtain human-readable error message
+ERR_error_string, ERR_error_string_n, ERR_lib_error_string,
+ERR_func_error_string, ERR_reason_error_string - obtain human-readable
+error message
=head1 SYNOPSIS
static buffer.
ERR_error_string_n() is a variant of ERR_error_string() that writes
at most I<len> characters (including the terminating 0)
-and truncates the resulting string if necessary.
+and truncates the string if necessary.
For ERR_error_string_n(), I<buf> may not be B<NULL>.
The string will have the following format: