I've just spent a good few hours trying to find any clues to the problem I was getting. du command would fail with a mysterious "fts_read" error, and there didn't seem to be any good answers on the net with explanations why. I figured someday this post will be found and might save someone a lot of time. It's a lengthy post and I believe the first one on this blog to be truly "advanced" in a technical sense.
If you're ever thought of summing up more than two numbers in shell script, perhaps this basic post will be a good start for your Unix scripting experiments.
Basic construction for summing up in shell scripts
In my Basic arithmetic operations in Unix shell post last year, I've shown you how to sum up two numbers:
Greetings everyone, today's post is going to be a bit different from the usual technical tips and tricks I share. This time around, I need a bit of help myself – and I hope many of you will be able to answer my questions. Bear with me: it's a lengthy post, but any help is GREATLY APPRECIATED!
Why am I asking these questions?
As you remember, a month ago I have offered invited all of the Unix Tutorial readers to learn Unix together. Everyone benefits from this – you get a chance to ask the questions which you always wanted answered, and I get to refresh my mind or even conduct a research on new topics just so that I can share the answers and solutions in the easiest to follow form.
I'm currently working on a members area for Unix Tutorial, which will eventually have a number of self-paced courses to help you improve your knowledge of Unix and get to the next level of productivity when solving technical problems.
Update: if you're interested in becoming a member, subscribe to the Unix Tutorial waiting list!
Today I was working on a script, and one of the subroutines needed simple seconds-based arithmetics with time. As you probably remember from my date and time in Unix scripts article, the easiest way to approach this task is to deal with the raw representation of date and time in Unix – the Unix epoch times. This post will show you how to convert standard dates into Unix epoch times in Perl.
Hi all, today I'm going to teach you not one, but two really cool things in one post! First, I'll introduce you to advanced memory usage stats available on Linux systems through /proc/meminfo file, and then I'll explain the basics of using the watch command.
Memory usage with /proc/meminfo
As you know, quite a few Unix-like systems use the so-called pseudo file systems like /proc. It's not a real filesystem, but just a convenient representation of processes managed by your Unix OS. In Linux systems, this directory also contains quite a few files allowing you to access various information about your system. /proc/meminfo is one of such files, it gives you access to most of the memory usage stats.
I've just been asked a question about changing the ownership of files from one Unix user to another, and thought it probably makes sense to have a quick post on it.
File ownership in Unix
Just to give you a quick reminder, I'd like to confirm that every single file in Unix belongs to some user and some group. There simply isn't a way to create a file without assigning ownership. I've briefly touched the topic of confirming file ownership in Unix before, so today I will simply build on that and show you how to change ownership of files.
Hi again, here's some more Unix articles which you'll probably find interesting and useful
Useful Unix tips
- uSbuntu Live Creator – boot your favorite OS from USB stick
- Backup del.icio.us bookmarks from Unix shell
If you have any useful articles you'd like to share – just leave links in the comments area.