Now I find myself looking at fc -l -d even when I don’t really need timestamps

% fc -l -d
[snip]
  356  14:56  vim sem.c
  357  18:09  gmake
  358  18:10  vim buffer.c

It is possible to get similar behavior with bash:

$ HISTTIMEFORMAT="%T " history 3
 1386  09:36:54 grep -rl afio .
 1387  09:37:55 vim ChangeLog
 1388  12:56:57 HISTTIMEFORMAT="%T " history 3

Where HISTTIMEFORMAT uses an strftime string.

Yet another useless bit of knowledge!

The release has only 2 real patches from 2.2.6, both for libltdl. See the announcement for slightly more detail.

Some users may be stuck using an older libltdl for whatever reason, for those users the same changes are provided by this untested patch.

[Update 2009-11-21]
The change to libltdl to not search in the current working directory for modules when lt_dlopen() is called without an absolute path breaks at least mpg123. This patch should work around the problem until the mpg123 folks fix it.

[Update 2009-12-02]
This release was to fix the now published CVE-2009-3736. If you have not already updated, doing so soon is advisable.

Indeed, it doesn’t work, and the reason is that ‘import locale’ is being called on a thread, which loads _locale.so, which requires that the CoreFoundation framework also be loaded. A simple reproducer in python is:

import os, sys
import threading
class Foo(threading.Thread):
	def __init__(self):
		threading.Thread.__init__(self)
	def run(self):
		import locale

t = Foo()
t.start()

The CoreFoundation framework must be loaded on the “main” thread, its initialization expects that, if it is loaded on some other thread, then it causes the application to exit rather abruptly. You can reproduce the same thing easily in C with:

#include <dlfcn.h>
#include <stdio.h>
#include <stdlib.h>
#include <pthread.h>

void* do_open(void* unused) {
        void * handle = dlopen("/System/Library/Frameworks/CoreFoundation.framework/CoreFoundation", RTLD_GLOBAL);
        if (! handle) fprintf(stderr,"ERROR: %s\n",dlerror());
        pthread_exit(NULL);
}

int main() {
        pthread_t t;
        pthread_attr_t a;
        if (pthread_attr_init(&a)) exit(1);
        if (pthread_create(&t,&a,do_open,NULL)) exit(2);
        pthread_attr_destroy(&a);
        sleep(5);
        return 0;
}

The failure can be avoided/worked around by ensuring that CoreFoundation is loaded on the main thread. For offlineimap, a simple way to do this is to put ‘import locale’ in the main script before init.startup is run. This will load _locale.so and thus CoreFoundation. CoreFoundation will run its initializers, and all will be well.

I am pretty sure that I have seen it documented somewhere that Apple’s frameworks must be loaded on the main thread, but I don’t seem to be able to find that documentation this morning (perhaps I just need more coffee?). In any case, loading any libraries that you need at application startup before you go spinning off threads is, in my opinion, a reasonable solution.

http://svn.macosforge.org/repository/odcctools/release/odcctools-20090808.tar.bz2

This is not a book review, I don’t think that I would be a good reviewer, being biased, as I am. Please find reviews elsewhere – although a quick look at amazon shows none there yet, unfortunately.

[EDIT June 22nd 2009] Found a review here http://hants.lug.org.uk/cgi-bin/wiki.pl?BookReviews/MacForLinuxGeeks. It’s the only one I could find.

Of course the reason that libtool did not use -exported_symbols_list in the first place is that Mac OS X 10.0 and 10.1 do not support it, and nmedit did the job just fine up to 10.5. Apple seems to have allowed nmedit to bitrot, it no longer does the same job that it did in 10.4. Filing a bug that you know in advance is just going to be closed with “use ld’s -exported_symbols_list flag” seems kind of pointless, but I guess I should do it anyway.

• http://www.mysql.com/products/tools/administrator
• http://yoursql.ludit.it

Not that I have tried either one, but they can’t be worse than an unmaintained binary that some random person (me) ported to Qt/mac years ago and then forgot about…