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2-Cent Tips

2-cent Tips: understand file system hierarchy right from the man pages

Mulyadi Santosa [mulyadi.santosa at gmail.com]

Fri, 23 Jul 2010 14:28:18 +0700

Probably one of my shortest tips so far:

Confused with all those /proc, /sys, /dev, /boot etc really mean and why on Earth they are there? Simply type "man hier" in your shell and hopefully you'll understand :)

-- regards,

Mulyadi Santosa Freelance Linux trainer and consultant

blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com

[ Thread continues here (4 messages/3.80kB) ]

2-cent tip: De-Microsofting text files

Ben Okopnik [ben at linuxgazette.net]

Fri, 23 Jul 2010 14:21:02 -0400

I was doing some PDF to HTML conversions today, and noticed some really ugly, borken content in the resulting files; the content had obviously been created via some Microsoft program (probably Word):

Just say ?<80><98>hello, world!?<80><99>?<80><9d>

I had a few dozen docs to fix, and didn't have a mapping of the characters with which I wanted to replace these ugly clumps of hex. That is, I could see what I wanted, but expressing it in code would take a bit more than that.

Then, I got hit by an idea. After I got up, rubbed the bruise, and took an aspirin, I wrote the following:

#!/usr/bin/perl -w
# Created by Ben Okopnik on Fri Jul 23 12:05:05 EDT 2010
use encoding qw/utf-8/;
my ($s, %seen) = do { local $/; <> };
# Delete all "normal" characters
$s =~ s/[\011\012\015\040-\176]//g;
print "#!/usr/bin/perl -i~ -wp\n\n";
for (split //, $s){ next if $seen{$_}++; print "s/$_//g;\n"; }

When this script is given a list of all the text files as arguments, it collects a unique list of the UTF-8 versions of all the "weird" characters and outputs a second Perl script which you can now edit to define the replacements:

#!/usr/bin/perl -i~ -wp

Note that the second half of each substitution is empty; that's where you put in your replacements, like so:

#!/usr/bin/perl -i~ -wp
s/\xFE\xFF//g;	# We'll get rid of the 'BOM' marker
s/?/&copy;/g;	# We'll make an HTML entity out of this one

Now, just make this script executable, feed it a list of all your text files, and live happily ever after. Note that the original versions will be preserved with a '~' appended to their filenames, just in case.

* Ben Okopnik * Editor-in-Chief, Linux Gazette * http://LinuxGazette.NET *

[ Thread continues here (5 messages/7.54kB) ]


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Published in Issue 177 of Linux Gazette, August 2010