Various RT doc fixes
RT1556: doc/crypto/threads.pod
RT2024: Missing pages mentioned in crypto.pod
RT2890: Wrong size in ERR_string_error description.
RT3461: Better description of PEM Encryption
(Jeffrey Walton <noloader@gmail.com>)
Also, fix up formatting and removed some code examples
that encourage unsafe patterns, like unencrypted private
keys (Rich Salz)
RT4240: Document some speed flags (Tomas Mraz <tmraz@redhat.com>)
RT4260: Fix return value doc for X509_REQ_sign and X509_sign
(Laetitia Baudoin <lbaudoin@google.com>)
Reviewed-by: Emilia Käsper <emilia@openssl.org>
diff --git a/doc/crypto/ERR_error_string.pod b/doc/crypto/ERR_error_string.pod
index 60df430..68d1a53 100644
--- a/doc/crypto/ERR_error_string.pod
+++ b/doc/crypto/ERR_error_string.pod
@@ -20,9 +20,12 @@
=head1 DESCRIPTION
ERR_error_string() generates a human-readable string representing the
-error code I<e>, and places it at I<buf>. I<buf> must be at least 120
+error code I<e>, and places it at I<buf>. I<buf> must be at least 256
bytes long. If I<buf> is B<NULL>, the error string is placed in a
static buffer.
+Note that this function is not thread-safe and does no checks on the size
+of the buffer; use ERR_error_string_n() instead.
+
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 string if necessary.
