SonicChicken

Apple Xcode, compilers and make and perl, oh my!

Fri, 12 Apr 2013 14:45:59 -0700

Yet another instance of Apple telling me what they are doing, and me failing to pay attention. sigh…

In this case, I recently “upgraded” my system at work, from the 3rd newest to the 2nd newest version of OS X. But after I did so, I lost all my developer tools (compiler, make, perl’s CPAN, etc.)

It turns out that all I needed to do was reinstall Xcode, but that’s now done via the App Store instead of the interwebz. Also, after installing Xcode, you need to run it so that you can have Xcode install the command line tools.

Go to /Applications/App Store and download/install Xcode
Launch Xcode (Applications/Xcode)
Open Xcode preferences, Downloads, Components.
On the Command Line Tools line, click the “Install” button.
Make sure the command line tools are in your PATH

Steps #1 and #4 take a bit of time, but once they were done I had a config.h and CPAN was working again.

Step #5 might take a little explanation. The command line tools that I was missing were make(1) and cc(1). I thought cc might be a little easier to find, so here’s what I did:

$ which cc
(nothing returned)
$ locate cc | grep /cc$
/Developer/usr/bin/cc
$ export PATH="$PATH:/Developer/usr/bin"

The first command verified that my PATH did not include the cc command. The second one (locate) showed me which directory it was in. And the third one added that directory to my PATH for the current session. Once you’ve verified that your tools are all working, copy that “export PATH…” command to your .bashrc file.

I might have avoided some of this trouble if I had kept up with What’s New in Xcode

Cueing up some Jim Croce… The meanest hunk o' woman That...

Wed, 27 Mar 2013 10:47:27 -0700

Cueing up some Jim Croce…

The meanest hunk o' woman
That anybody ever seen
Down in the arena

Sharing mail.app Act-On rules

Wed, 27 Mar 2013 10:42:34 -0700

One of the tools I make the most use of is email. I like Apple’s mail.app (which comes with OS X), but it’s vastly improved with a couple of extras from indev.ca: Mail Act-On and MailTags. I use this combination on all my Macs, and the only major hurdle is keeping the Act-On rules the same on all my systems. A quick browse of the indev.ca knowledge base brought me to Manually moving Mail Act-On rules. This turns out to be fairly easy to do, if you designate one of your systems as the “master”. Just copy the following files from that system to your “slave” systems:

~/Library/Mail/Indev/ActOnRules.plist
~/Library/Mail/Indev/OutboxRules.plist
~/Library/Mail/Indev/MailTagsInboxRules.plist

Remember that the Finder won’t show your ~/Library folder unless you explicitly “Go To Folder…” (shift+apple+G on keyboard).

Handy one-line scripts for AWK

Tue, 08 Jan 2013 12:21:20 -0800

Handy one-line scripts for AWK

Advanced bash scripting

Mon, 17 Dec 2012 09:41:06 -0800

The section on advanced bash scripting tops is always worth going back for a re-read! There are a lot of nuggets of platinum among all the gold. :D

Of course, this assumes familiarity with the previous sections of the bash scripting guide.

Declare your Pod encoding

Mon, 10 Dec 2012 16:07:00 -0800

Earlier this year, a minor change to Pod::Simple caused brian d foy’s Mac::Errors module to fail during testing. The underlying problem is an ASCII/UTF-8 issue. One might expect the utf8 pragma to fix this, but remember that POD ignores all the code outside of POD elements.

Aristotle Pagaltzis makes an excellent point in the comments on bdf’s post, mentioning that it’s a Bad Idea to mix your POD and program text encodings.

Since I’m using a Mac, UTF-8 characters are pretty likely to end up in my code and/or POD. It seems prudent to follow the suggestions from bdf’s article:

In the source code, include the utf8 pragma: > use utf8;

Declare your Pod encoding as utf8: > =encoding utf8

(update 2013-03-26) The encoding command has been a part of perlpod since at least version 5.8.8, based on that version’s documentation:

http://perldoc.perl.org/5.8.8/perlpod.html

According to that documentation, the encoding should be the first pod directive. It can appear anywhere (not necessarily within a documentation block), but it must only appear once.

Since that’s a perlpod command, it needs its own paragraph (i.e. two consecutive newlines). And since the “use utf8” and “=encoding utf8” work together, it’s probably a good idea to include this in the header:

use utf8;

=encoding utf8

The blank lines before/after encoding must be completely empty. An easy way to check that (and many other perlpod requirements) is podchecker(1).

Unix `find' without subdirectory traversal

Wed, 14 Nov 2012 16:19:00 -0800

I love the `find(1)’ command! But sometimes I don’t want the default fully-recursive behavior. For example, today I wanted to do something with all of my “dot files” without affecting “dot directories” (such as .ssh) or their contents:

find $HOME/.* -prune ! -type d -exec ls {} \;

The `ls’ command is just for demonstration purposes. Substitute with a useful command of your choice.

Math geeks

Thu, 08 Nov 2012 14:30:50 -0800

Q: Why do math geeks get Halloween and Christmas confused?

A: Because 25_dec = 31_oct.

Homebrew Packaging Guide

Tue, 06 Nov 2012 11:22:58 -0800

Homebrew Packaging Guide:

I originally found this on Con Poco Coco’s tumblog, but the link was broken. The URL for afp548.com seems to be the same material. Below is the original post from Con Poco Coco:

This guide is for setting up homebrew to build individual packages that can be deployed with munki or ARD.

(404 URL: http://osxdeployment.com/wiki/Homebrew_Packaging_Guide)

Revisiting Those Pesky Firmware Passwords

Tue, 06 Nov 2012 11:14:48 -0800

conpocococo:

Charles’s Krypted.com blog has a useful post about setting Apple hardware firmware passwords. The efipw.py script works great on the MacBook Pro (13-inch, Mid 2010) machines I tested it on. However version 0.2b does not work on newer models (see below for list) as Paul Makowski notes on the project page. Interestingly enough the python script is still able to decrypt the password on the newer models. Thankfully one must run it as root (or via sudo) to do that otherwise this whole firmware lock exercise would be moot.

The Apple Way(tm) of setting EFI firmware passwords is to use an application on the install DVD called Firmware Password Utility. Since I have gone to all the trouble of setting up DeployStudio and Munki to automate the management of the hundreds of Macs under my care, it is poor option to boot from the DVD and manually set the firmware password. There are many reasons for this, but the number one is manual entry leads to errors. (I should note, not having verification steps also leads to errors, but that is for another blog post.)

What is an automating loving sysadmin to do?

Read More

Backing up and restoring SSL certificates in 10.5 and 10.6

Tue, 06 Nov 2012 11:12:59 -0800

Backing up and restoring SSL certificates in 10.5 and 10.6

Con Poco Coco: Managing sshd on Mac OS X Via the Command Line

Tue, 06 Nov 2012 11:09:00 -0800

Con Poco Coco: Managing sshd on Mac OS X Via the Command Line:

conpocococo:

This information is all out there, but there is enough cruft mixed in, that I’m making my own post.

GUI Way

With mouse and keyboard, you can enable/disable sshd on Mac OS X by going to System Preferences -> Sharing. Check or uncheck Remote Login. You also have the option of limiting who can…

Perl EDI module

Thu, 25 Oct 2012 10:37:00 -0700

The only EDI module I’ve found for Perl is http://search.cpan.org/~kraehe/XML-Edifact-0.47/XML/Edifact.pm

This module converts an EDI document to/from XML. Use other XML modules to do actual processing.

Seems to be unmaintained, or perhaps it’s achieved perfection? ;)

Links for the twig module (Perl XML)

Thu, 25 Oct 2012 10:28:00 -0700

XML::Twig is a memory-efficient tree-based XML parser/processor module.

The Twig home page: http://www.xmltwig.org/xmltwig/ <— START HERE!

Tutorials (old): http://www.xmltwig.org/tutorial/

An example: http://stackoverflow.com/questions/10239920/using-perl-xmlsax-to-modify-xml-documents (I heart stackoverflow!)

Twig 3.41 (latest as of today, possibly unstable?) http://search.cpan.org/~mirod/XML-Twig-3.41/Twig.pm

If XML::Twig can’t do what you need, check http://search.cpan.org/~shlomif/XML-LibXML-2.0008/LibXML.pod — it’s very “featureful”, may take a while to master.

Arduino programming with MacOSX

Mon, 15 Oct 2012 09:27:43 -0700

Arduino programming with MacOSX:

This guide describes setting up the Arduino programming environment on Mac OS X.

folhadespaulo: Paraquedista rompe a barreira do som em queda...

Mon, 15 Oct 2012 09:23:09 -0700

folhadespaulo:

Paraquedista rompe a barreira do som em queda livre ao saltar da estratosfera.

Safe return after jumping from ~128,000 ft!

Output files by date

Tue, 26 Jun 2012 19:18:00 -0700

This evening I needed to cat(1) a bunch of files, in date order. All of the files had “LABEL” in their name, but the names’ lexical sort didn’t put them in date order. This is pretty simple in bash, using the “-t -r” switches on ls and using a for-loop:

for F in `ls -t -r *LABEL*`; do
    echo "---- file $F ----"
    cat $F
done

Perhaps a bit trivial, but some may find it useful. Enjoy!

Log space usage

Thu, 14 Jun 2012 13:48:00 -0700

Last month I posted a tiny awk script to calculate the sum of a column of numbers. The context there was a glob of directory names. But today I had a slightly different problem — I needed to get total space used by all of the logfile directories within a tree. Fortunately, all the directories are named “logs”. Unfortunately, they aren’t always at the same depth within the tree so I can’t use a wildcarded path, e.g. */logs. But it’s easy enough to manage with find(1) and the awk scriptlet that I posted last month:

find /some/directory/path/ -type d -name logs -prune -exec du -s -k {} \; | awk '{total+=$1} END {print total}'

This looks within the /some/directory/path/ tree for directories (-type d) with filename logs (-name logs). Since I am passing these files to du(1), I don’t want the find utility to look within the logs directories (-prune). I pass the found directories to du (via -exec du -s -k {} \;), and at this point it’s effectively the same thing I did last month.

Using Safari as an RSS reader

Fri, 25 May 2012 16:11:57 -0700

Using Safari as an RSS reader:

Dave Taylor has a very concise article on using Apple’s Safari browser as an RSS reader.

Known hosts' ASCII art

Wed, 23 May 2012 15:30:54 -0700

Want to see the ASCII art of all the systems in your ssh known_hosts file?

$ ssh-keygen -lv -f ~/.ssh/known_hosts

I know this works on recent versions of FreeBSD and Mac OS X. It probably also works on other BSD’s and possibly the Linux distros.

(Warning: Seeing a whole bunch of cruft in your known_hosts(5) file may cause you to spend considerable time cleaning it up! ;)