ipython problem

[SylvainT]

Hey all!

Finally I'm finding some time to play with all the programming stuff I learnt during last month's great training session...

And here is my first (very basic) question...

The ipython version that comes with BV (0.8.2; launched from the BV menu, the BV version being 3.2.0) doesn't allow me to use all the basic nice shell features that we all need (top-arrow to get back to the previously typed command, tabulation to use the completion etc.). I tried to system-wide ipython (0.10; I'm on ubuntu 9.10), and I have all these...

Any clue why?

Sylvain

[SylvainT]

hmmm... google says it seems to be a readline-related problem...

see for example: http://mail.scipy.org/pipermail/ipython ... 05829.html
(his problems are identical to mine: "pressing up arrow prints ^[[A"; and also "down arrow prints ^[[B", and tab doesn't work...)

but why is it happening? and how to fix it?

[riviere]

Hi Sylvain,
To check if the readline module can actually be imported, from the ipython of the brainvisa package, try it:

Code: Select all

In [1]: import readline
In [2]:readline.__file__
Out[2]:'/home/appli/cartopack-Fedora-4-i686-3.2.0-2009_11_05/lib/python2.5/site-packages/IPython/rlineimpl.pyc'

In [3]:readline._rl
Out[3]:<module 'readline' from '/home/appli/cartopack-Fedora-4-i686-3.2.0-2009_11_05/lib/python2.5/lib-dynload/readline.so'>
In [4]:!ldd -r /home/appli/cartopack-Fedora-4-i686-3.2.0-2009_11_05/lib/python2.5/lib-dynload/readline.so
        linux-gate.so.1 =>  (0x0096f000)
        libreadline.so.5 => /lib/libreadline.so.5 (0x0041f000)
        libncursesw.so.5 => /lib/libncursesw.so.5 (0x00502000)
        libpython2.5.so.1.0 => /home/appli/cartopack-Fedora-4-i686-3.2.0-2009_11_05/bin/../lib/libpython2.5.so.1.0 (0x00e46000)
        libpthread.so.0 => /lib/libpthread.so.0 (0x0075d000)
        libc.so.6 => /lib/libc.so.6 (0x005a5000)
        libtinfo.so.5 => /lib/libtinfo.so.5 (0x00110000)
        libdl.so.2 => /lib/libdl.so.2 (0x0088d000)
        libutil.so.1 => /lib/libutil.so.1 (0x00129000)
        libm.so.6 => /lib/libm.so.6 (0x0012d000)
        /lib/ld-linux.so.2 (0x009f7000)

If all this is OK, I guess it's something else.
If not, I guess one of the required libs is missing or doesn't have the right version.
Which Linux distribution/version are you using ?
For instance on my Fedora 12, I see that this libreadline.so.5 is an old one:

Code: Select all

% rpm -qf /lib/libreadline.so.5
compat-readline5-5.2-17.fc12.i686
% rpm -q readline
readline-6.0-3.fc12.i686

So you will have to install this compat-readline5 package. I guess there are equivalents on other distributions.
Sorry, this lib was a pretty stable component of the system until now (libreadline 6 is still not present on Fedora 11, libreadline 5 is the default one), so we didn't include it in our packages.

Denis

[SylvainT]

Hi Denis, thanks for your answer, that was indeed a problem of version of libreadline!

The first line of your suggested test ('import readline') failed, telling me that libreadline.so.5 was not found... And indeed, only libreadline6 was installed on the system... So I installed libreadline5 and everything's fine now... I'm on the latest Ubuntu (9.10)

Cheers,

Sylvain (still new to python and not familiar with debugging practices...)