I did comment base64 command line in http://wiki.opensslfoundation.com/index.php?title=Command_Line_Utilities.
So I issue a Warning when using openssl base64 decoding :
openssl base64 -e <<< 'Welcome to openssl wiki'
openssl base64 -d <<< 'V2VsY29tZSB0byBvcGVuc3NsIHdpa2kK'
Welcome to openssl wiki
warning base64 line length is limited to 64 characters by default in openssl :
openssl base64 -e <<< 'Welcome to openssl wiki with a very long line
openssl base64 -d <<< 'V2VsY29tZSB0byBvcGVuc3NsIHdpa2kgd2l0aCBhIHZlcnkgbG9uZyBsaW5lIHRoYXQgc3BsaXRzLi4uCg=='
=> NOTHING !
to be able to decode a base64 line without line feed that exceed 64 characters use -A option :
openssl base64 -d -A <<<
Welcome to openssl wiki with a very long line that splits...
This is anyway better to actualy split base64 result in 64 characters lines since -A option is BUGGY ( limit with long files ).