MySQL Bugs: #63544: Problem with keystroke handling from XTERM

Bug #63544	Problem with keystroke handling from XTERM
Submitted:	2 Dec 2011 16:48	Modified:	27 Dec 2011 11:41
Reporter:	Emanuele Tomasi	Email Updates:
Status:	Not a Bug	Impact on me:	None
Category:	MySQL Server: Command-line Clients	Severity:	S3 (Non-critical)
Version:	5.1.59	OS:	Any
Assigned to:		CPU Architecture:	Any
Tags:	alt, client, keys, xterm

Description:
When I start a connection from Xterm with mysql command I can't use Alt+key movements (emacs mode for readline). In addiction, when I close mysql client it let my Xterm in trouble: I no longer can use the shortcut above.

I use Slackware64.

How to repeat:
In my Xterm session I do:
mysql

Suggested fix:
I can solve this problem if I set TERM variable to 'linux' instead 'xterm'. This alias work fine for me:
alias mysql='TERM=linux mysql'

If the problem is solved by setting other value for TERM, why do you think this is a problem in mysql client and not in xterm, for example? 

Can you use the same keystrokes in other client that uses readline, like bash shell, while in xterm?

Hi Valeriy,
yes, before I run mysql client I can use readline keystrokes in bash shell within xterm.

Regards,
Emanuele

Thank you for the feedback.

Please send your readline configurtion file and output of command \s in MySQL command line client.

inputrc for readline

Attachment: inputrc (application/octet-stream, text), 951 bytes.

Output of '\s' command in mysql client

Attachment: command (application/octet-stream, text), 1.21 KiB.

Hi Sveta,
I attached the files you requested.

Best regards,
Emanuele

Thank you for the feedback.

I can not repeat described behavior with current development sources. Please try with current version 5.1.60 available from dev.mysql.com/downloads and if problem still exists provide compile options you use to build MySQL (I saw "Source distribution" in the "\s" output, so I assume you build yourself).

Sveta,
I don't think that is a compilation problem. I don't build mysql by myself, instead I use the package provided by Slackware. The build options are:
---
/configure \
  --prefix=/usr \
  --libdir=/usr/lib${LIBDIRSUFFIX} \
  --with-mysqld-user=mysql \
  --with-unix-socket-path=/var/run/mysql/mysql.sock \
  --localstatedir=/var/lib/mysql \
  --mandir=/usr/man \
  --infodir=/usr/info \
  --enable-assembler \
  --without-debug \
  --enable-thread-safe-client \
  --with-extra-charsets=complex \
  --with-ssl=/usr \
  --enable-largefile \
  --with-innodb \
  --with-readline \
  --build=$ARCH-slackware-linux
---

The problem seems be something about charset. I have LANG setted on 'it_IT@euro' (note that I don't use UTF8). When I run mysql client seems it use UTF8 charset because I see, e.g. for alt+f the symbol 'â' and for alt+b the symbol 'æ'. Again, when I quit from client, alt+backspace do nothing but after this I can go back beyond prompt. E.g.:
Normal promp:
=>
If I press alt+backspace all is the same, but after, if i press backspace:
=

I hope this help you to find the "bug",
Emanuele

Emanuele,

thank you for the feedback.

If you don't use UTF8, please, run SET NAMES latin1 and check if this solves the problem. I think collation latin1_general_ci would perfectly work for Italian.

No Sveta,
SET NAMES doesn't resolve the problem. But, as I said, setting TERM variable to 'linux' is a good workaround, does this help you?

Emanuele

Thank you for the feedback.

I still can not repeat described behavior. Please try with our binaries and version 5.1.60 available from dev.mysql.com/downloads and inform us if problem still exits. You can use generic Linux binaries.

Sveta, I didn't find the 5.1.60. I tried 5.1.59 found in this location:
http://downloads.mysql.com/archives.php?p=mysql-5.1
but the problem still exists. I report what I did:
---
#> cd /usr/local
#> ln -sf /tmp/mysql-5.1.59-linux-x86_64-glibc23/bin mysql
#> cd mysql/bin
#> ./mysqld_safe --datadir=/var/lib/mysql --pid-file=/var/run/mysql/mysql.pid --skip-networking
---
And then with normal user:
---
$> cd /usr/local/mysql/bin
$> ./mysql
Welcome to the MySQL monitor.  Commands end with ; or \g.
Your MySQL connection id is 1
Server version: 5.1.59 MySQL Community Server (GPL)

Copyright (c) 2000, 2011, Oracle and/or its affiliates. All rights reserved.

Oracle is a registered trademark of Oracle Corporation and/or its
affiliates. Other names may be trademarks of their respective
owners.

Type 'help;' or '\h' for help. Type '\c' to clear the current input statement.

mysql> \s
--------------
./mysql  Ver 14.14 Distrib 5.1.59, for unknown-linux-gnu (x86_64) using readline 5.1

Connection id:          1
Current database:
Current user:           spina@localhost
SSL:                    Not in use
Current pager:          stdout
Using outfile:          ''
Using delimiter:        ;
Server version:         5.1.59 MySQL Community Server (GPL)
Protocol version:       10
Connection:             Localhost via UNIX socket
Server characterset:    latin1
Db     characterset:    latin1
Client characterset:    latin1
Conn.  characterset:    latin1
UNIX socket:            /var/run/mysql/mysql.sock
Uptime:                 1 min 2 sec

Threads: 1  Questions: 4  Slow queries: 0  Opens: 17  Flush tables: 1  Open tables: 4  Queries per second avg: 0.64
--------------

mysql> useâ
---

As you can see I typed 'use' plus 'alt+b' and the terminal shows 'useâ'.

If you write the right location for the version 5.1.60 I'll try it too.

Best regards and merry (past) Xmas,
Emanuele

Sveta, I resolved the problem. It's not a mysql bug but a mistake in readline configuration. I wrote an email to Thomas Dickey, the developer of xterm, and he linked me to this page:
http://invisible-island.net/ncurses/ncurses.faq.html#bash_meta_mode

For my PC, the correct configuration for readline within xterm is:
set convert-meta On
set input-meta Off
set output-meta Off

Best regards,
Emanuele

I forgot to say that is the default readline configuration (readline(3)), but, strangely on my PC I had:
---
convert-meta is set to `off'
enable-meta-key is set to `on'
input-meta is set to `on'
meta-flag is set to `on'
output-meta is set to `on'
---

Emanuele