user9474's questions

On my Mac terminal, printing UTF-8 works in general, but the less doesn't work correctly.

So this works correctly:

$  echo -e '\xe2\x82\xac'   
€

but piping it into less gives something like this:

$  echo -e '\xe2\x82\xac' | less  
<E2><82><AC>

How can this be fixed?

For diagnostics:

I'm using Mac OS 10.6.8. less version 418, Terminal 2.1.2 (273.1).

The output of my locale is this:

$ locale
LANG="en_US.UTF-8"
LC_COLLATE="C"
LC_CTYPE="C"
LC_MESSAGES="C"
LC_MONETARY="C"
LC_NUMERIC="C"
LC_TIME="C"
LC_ALL="C"

How can I output the real time a command takes (and nothing else)?

Example:

This won't work:

$ time -p sleep 2 | grep real
real 2.00
user 0.00
sys 0.00

I want something like:

$ print-real-time sleep 2
2.00

For a certain directory DIR on my system, the ls --color=always takes about 8 seconds, although it contains less than 10 files and subdirectories. Without the color argument it takes no time.

Why would ls take so long with the color argument, and how can I find out what exactly is taking so long? It is probably some subdirectory in DIR that is mounted, but how can I find out which one is the troublemaker?

I have SSH access to my university account using SSH without password. That's working so well that I even forgot that password altogether.

Now I have a new computer and would like to access my university account from there. But I can't without the password! Can I transfer the password-less authentication from my old computer to the new?

Of course, I could also ask the university sysadmins to create a new password for me, but they are known to be very slow, so it might take a few days before I can access.

When I open a new window in GNU screen, it runs .bashrc but not .bash_profile. In my setup, this results in some environment variables not being set up correctly in that window.

How can I tell GNU screen to always run .bash_profile instead of .bashrc on opening a new window? (Please don't tell me to just call .bash_profile from my .bashrc :)

I would like to configure GNU screen such that it stores the command histories of all the different windows in different files.

I know by default GNU screen does not store the command histories (of its different windows) in a file at all (it stores them in memory instead), but it might be possible to tell it to store them in files instead?

The different command history files should have the names <session>.<window>.history, or similar.

Does anyone have an idea how to do that?

(Just to be clear, I want each GNU screen window to write a different file. I like that each window has a different history, and I typically run different types of commands in the different windows.)

I am trying to call system commands from perl, using system().

That usually works fine, but when I don't start the perl script myself, but have a compiled C program run it using the C popen() function, then perl is not able to execute its system commands. Perl's system() then returns with exit code 13.

It works only if I use the backticks in Perl, instead of system. Does anyone know why?

Is it dangerous to have several parallel jobs create the same directory using mkdir -p? (This is under Linux.)

In my case, I send many jobs to a SUN grid to process them in parallel, and some of these jobs start by creating a certain directory foo. So, the execution of the different mkdir commands might happen at exactly the same time ...

I have this line in my .emacs file:

(tool-bar-mode 0)

because I hate the toolbars in my GUI emacs (/Applications/Emacs.app/Contents/MacOS/Emacs).

But when I start up my other, text-based emacs in the terminal (/opt/local/bin/emacs) it complains about that command:

Symbol's function definition is void: tool-bar-mode

How can I add an if condition so that it executes the tool-bar-mode command only when I'm in the GUI emacs?

Thanks!

I need to add a directory to my PATH variable on Mac OS.

I added it in .bash_profile and .profile, and that works for the terminal.

But Emacs (http://emacsformacosx.com) still does not use the new PATH variable. (I'm trying to run latex from emacs, but it's not finding the command in my /usr/local/bin, which I'm trying to add to the PATH ...)

I even logged out and back in, but still no luck.

Any suggestions?

How do you migrate a part of an SVN repository into a new repository?

To migrate the contents of a complete SVN repository into a new repository, one has to dump the old repository first:

svnadmin dump /path/to/repository > repository-name.dmp

and then load it into the new one using svnadmin load.

But I'm not sure how to just migrate a part. Do I still have to dump the whole thing? Do I grep for the part that I want?

To just dump myproject, I tried this, but it didn't work:

svnadmin dump /path/to/repository/myproject

Any ideas?

I use GNU screen with 5 different sessions, each of which stores its own command history. But often I don't find a command in the history, although I'm sure I've used it exactly in the session I'm currently in, a few weeks ago.

It seems there is a hard limit on the history size? How can I set that to infinity?

A related question: How can I control where the history of a session is stored? Often, our sysadmin reboots the computer(s) and I lose all my sessions, and I have to do screen -wipe because the sessions are corrupted. Then, all histories are gone. :( I'd like to find the stored histories in that case and bind them in a newly created session.

P.S.: I use bash in all screen sessions.

UPDATE: I am not asking about how to unify the session histories. Just, I want each session to have an infinite history, and I want to be able to 'load' that history into a new session, should the old one get corrupted or deleted.

UPDATE 2: You've probably figured out: When I said I use GNU screen with 5 different sessions I really mean a GNU screen session with 5 different windows in it. Sorry.

I have a unicode file that contains Chinese characters. I have a local and a remote copy of it.

When I use less on the local file the characters are shown properly:

奥尔德林

However, when I ssh to the remote machine and look at the remote version of the same file the characters are just shown like this instead:

<E5><A5><A5><E5><B0><94><E5><BE><B7><E6><9E><97>

How can I properly view the remote unicode file (when connected via ssh)?

(I'm using the standard terminal application on Mac OS.)

I have a URL that I would like to share with my friend who needs the information on it, but I do not want the public to see it.

The URL refers to an index.html, which is in my public_html and readable for everyone, say:

public_html/secret23/index.html

Nothing links to that URL `.../~dehmann/secret23'. Can I trust that search engines will not find and index it? So no one except my friend will be able to see it? (Assume that my friend will never leak the URL.)

I think the answer is yes, since Google also uses this technique in Picasa and Google Documents, to publish documents, where the user doesn't want search engines to see it. But I just want to make sure this is how it works (before my sensitive information is out there for everyone to see).

UPDATE: To clarify, my question boils down to: Is it true that Google (or, anyone) can not recursively list the content of my public_html? Or can they?