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Showing posts from 2011

Resizing the system NTFS partition on Windows XP

I didn't find a way to grow the boot partition on a live system (I think OS X has been able to do that for some time now?). I used BootIt , free for this kind of partition work. Quick download, quick self-install on a USB stick, reboot, unnervingly unresponsive while working, but finally problem-free. In my case I was growing the boot partition into free space. And this XP uses some Intel SATA AHCI driver, and installed in a non-standard way at that, which made me a bit weary. But everything turned out right. The next best option seemed to be GParted Live, which also has an easy way to be installed on a USB stick via TuxBoot.

Directory permissions vs local Portfiles in MacPorts

~/MacPorts/ports$ sudo port install socat --->  Computing dependencies for socat could not read "/Users/mija/MacPorts/ports/sysutils/socat/Portfile": permission denied I was having strange problems to use a locally edited portfile. Turns out the permissions were wrong in a directory in the path; each of the directories should have at least o+rx permissions, and strangely my $HOME had none of those (strange because other users in my computer had o+rx, admins or not). Note that MacPorts lately (from 2.0?) has started to use the user nobody at some points of its workings, and root at others; in this case the user nobody was the one unable to reach the Portfile. A way to check what this user sees is " sudo -u nobody ls -leda@ /Users/mija/blabla ". A workaround is setting macportsuser in /opt/local/etc/macports/macports.conf to root, but that's not a good idea. MacPorts is doing the the sensible thing, de-escalating privileges when they are not needed; th

Custom software for interfacing via USB with multimeters UNI-T UT81B

These multimeters are rather pocket oscilloscopes. Quite an interesting package. And the possibility of interfacing via USB with a computer should multiply the possibilities. Alas, the included software could hardly be crappier. (why do so many manufacturers do something justifiably interesting and then neuter it by blowing up what should be a minor part of the whole?)

Límites absurdos de longitud de paths en APIs de Windows

Ordenando cosas viejas me he encontrado con un problema interesante que tuvimos en los tiempos de gvSIG (hace unos 4 años)... Problema: si se intenta descomprimir el ZIP en un Windows, nos encontramos con la incapacidad de Windows de crear ficheros con path completo de más de 260 chars. Esto sucede tanto en NTFS como en FAT, y es un problema (por ejemplo) si se quiere descomprimir el ZIP en un Windows para meterlo en una unidad USB o un CD / DVD. No es una limitación de FAT: la copia o descompresión se puede hacer en un OS no-Windows y va bien. Es una limitación de API de Windows (como mínimo incluyendo Windows 2003 Server): aunque filenames pueden ser de mas de 255chars, paths completos no pueden superar 260 chars. http://msdn2.microsoft.com/en-us/library/aa365247.aspx

Steve Jobs and the Monomyth

Just realized that Steve Jobs' trajectory could be somewhat compared to the Monomyth : the fall from grace when fired from Apple, the struggles in NeXT and Pixar which ended nicely but were quite a bet, the coming back to the beleaguered Apple (look, that infamous sentence!) and the multiple concurrent struggles (Mac vs Windows, iPod vs constellation of MP3 players, iPhone vs telephone industry, iPad vs computer industry), and the final fight against cancer itself. (What a crescendo!) Maybe that's why even people who only passingly knew about the story were hit by the news of his death? Maybe just because he was that "Hero" fighting all those impossible fights - and winning! Mhm, now I am worried about what kind of film are they wanting to make about him... I can't really imagine it being interesting nor good, but if they think about the Monomyth angle, I can imagine it getting crappy.

canalmac.es y #mac en irc-hispano

Escribo esto por si alguien intenta googlear sobre Antispasm (yo!) en el canal #mac en irc.irc-hispano.org, o en canalmac.es . Después de unos cuantos años allí, y de incluso plantearme escribir en canalmac.es , la cosa se ha puesto inaguantable hasta el punto de tener que escribir esto. Si buscas consejo o ayuda para algún problema, primero que nada (y para mantenerme en mi línea): has googleado ya? ;P Y si ya lo has hecho, lo siento pero en #mac dudo que encuentres nada de interés. Poco a poco hay menos gente, y hace tiempo que no veo a nadie con idea; el último creo que era yo, modestia aparte ;P, y cada vez estoy menos por allá. Hay dos o tres personas allí que trabajan en IT de una forma u otra, pero por lo que preguntan o dicen de vez en cuando yo no confiaría en ellos, por lo menos cuando se trata específicamente de Mac OS X. Y concretamente, y ésto es lo peor: ojo con Tuti. Es operador allí, y es el... editor? de canalmac.es. Es usuario de Mac desde hace tiempo, pero creo

dtrace'ing paging to disk

How to know which processes are paging to/from disk (as opposed to other VMM management) in OS X, and how much exactly: sudo dtrace -n maj_fault'{@[execname] = count()}' reference (with examples and other options): http://wikis.sun.com/display/DTrace/vminfo+Provider I had been meaning to look for ways to do this, and tried some of the tools included in OS X (Activity Monitor, top, Instruments, vm_stat, vmmap, top, ...). But nothing really helped, and/or seemed to miss the exact level of information I was targeting (only resulting in real I/O; relationship between I/O and process; realtime... ). Finally I had the inspiration to google for "dtrace pagefaults". Bingo. (dtrace in this example isn't realtime, but is the best approximation so far, and I'm guessing some tuning should fix it. Heck, it's a one-liner!) Learning dtrace is still something I'd love to do, and once again it is tempting me to let it jump to the front of queue... (Mhm, wi

Compiling Transcode 1.1.6 and 1.2 in OS X

(express post, too much time spent on this but too much work spent to let it slip without benefitting someone else) 1.1.6 is not released, had to be hg-cloned. In fact, the repository looks like the 1.1.6 tag was at some moment added but then deleted?? That branch also has the latest video stabilization, no idea yet if it is also in 1.2 Can be compiled. Get the hg repository via hg itself, not one of the zip/bz/etc packaged from the website since the compilation scripts expect to find the .hg files. Read the README and INSTALL, you'll need to create the configure yourself (easy, just read) I am using MacPorts, and even installed the included Transcode 1.1.5, so all the requirements are already installed. Most of the expected work was about configuring tne non-macports transcode to use the /opt dirtree. (Incidentally: 1.1.5 has horribly mismatched documentation, I have had to resort to using strings and source code to understand what some of the utils were supposed to

Discos duros dañados, salvar datos y huir de SpinRite

Últimamente me he encontrado a gente hablando de usar SpinRite para recuperar discos duros (incluso en Macs!), así que quizás ayude si cuento mi experiencia. Hace unos años (quizás 5?), el disco duro de mi iMac G3 de por entonces empezó a fallar. El ordenador se quedaba de repente congelado, sin responder a nada durante alrededor de 10 minutos, y luego de repente continuaba funcionando como si nada. Si recuerdo correctamente, las pausas siempre eran igual de largas, y ni siquiera respondía al ratón. No recuerdo si el disco hacía algún ruido extraño. Cómo supe que era el disco duro? Probé con algún CD o DVD de Linux y todo parecía ir bien, excepto al acceder al disco duro. Quería sacar los datos, así que empecé a buscar posibilidades. Una cosa que encontré fue SpinRite, que según lo que decía en su página web, sonaba a magia... lo cual en cosas de informática no es buena señal, creo yo. Se supone que SpinRite "revive" el disco duro. Pero bueno, llevaba tiempo con curiosi

"OpenSSL speed" on iPhone 4

A test I thought could be interesting to get some (diffuse) idea of the processing power of the iPhone 4: Mijails-iPhone:~ mobile$ uname -a Darwin Mijails-iPhone 10.4.0 Darwin Kernel Version 10.4.0: Wed Oct 20 20:14:45 PDT 2010; root:xnu-1504.58.28~3/RELEASE_ARM_S5L8930X iPhone3,1 arm N90AP Darwin Mijails-iPhone:~ mobile$ openssl speed To get the most accurate results, try to run this program when this computer is idle. Doing md2 for 3s on 16 size blocks: 113903 md2's in 2.93s Doing md2 for 3s on 64 size blocks: 59789 md2's in 2.96s Doing md2 for 3s on 256 size blocks: 20740 md2's in 2.94s Doing md2 for 3s on 1024 size blocks: 5722 md2's in 2.95s Doing md2 for 3s on 8192 size blocks: 741 md2's in 2.95s Doing md4 for 3s on 16 size blocks: 962184 md4's in 2.99s Doing md4 for 3s on 64 size blocks: 808365 md4's in 2.94s Doing md4 for 3s on 256 size blocks: 553565 md4's in 2.94s Doing md4 for 3s on 1024 size blocks: 251644 md4's in 2.96s D