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1500 questions
97
votes
8 answers
Colors in Man Pages
When I look at a man page in my 'console' (not an xterm) I see some coloration, but I don't get this in my xterm's (e.g. konsole) is there any way I can enable this? hopefully a fairly simple solution?
xenoterracide
- 59,188
- 74
- 187
- 252
97
votes
8 answers
Make a symbolic link to a relative pathname
I can do this:
$ pwd
/home/beau
$ ln -s /home/beau/foo/bar.txt /home/beau/bar.txt
$ readlink -f bar.txt
/home/beau/foo/bar.txt
But I'd like to be able to do this:
$ pwd
/home/beau
$ cd foo
$ ln -s bar.txt /home/beau/bar.txt
$ readlink -f…
Humphrey Bogart
- 1,541
97
votes
3 answers
What is the point of the `yes` command?
This question concerns the yes command found in UNIX and Linux machines: Basically, what is the point (if any) and history of this tool? Are there practical applications for it? Can an example be shown where it is useful in a script or chained (via…
Jaryd Malbin
- 1,041
96
votes
6 answers
Is there a way to determine the optimal value for the bs parameter to dd?
On occasion I've seen comments online along the lines of "make sure you set 'bs=' because the default value will take too long," and my own extremely-unscientific experiences of, "well that seemed to take longer than that other time last week" seem…
user4443
96
votes
6 answers
How to cause kernel panic with a single command?
Is it possible to cause a kernel panic with a single command line?
What would be the most straightforward such command for a sudoing user and what would it be for a regular user, if any?
Scenarios that suggest downloading something as a part of the…
Desmond Hume
- 2,798
96
votes
5 answers
How to run time on multiple commands AND write the time output to file?
I want to run time command to measure time of several commands.
What I want to do is:
Use the time command to measure the time it takes to run multiple commands together
Write only the time output to a file
Write the stderr of all commands I am…
Karel Bílek
- 1,951
96
votes
6 answers
How to COMPLETELY turn off system beep sounds forever for good for real
I use Nautilus to explore my files. I use a Debian-based OS with KDE Plasma 5.
I use the keyboard a lot. When I press the key up when navigating files, if I'm already at the extremity of the list of files, Nautilus sends a big system beep which I…
96
votes
8 answers
Nano - jump to end of file
I have some long log files. I can view the last lines with tail -n 50 file.txt, but sometimes I need to edit those last lines.
How do I jump straight to the end of a file when viewing it with nano?
payloc91
- 2,329
96
votes
19 answers
How to check if a pipe is empty and run a command on the data if it isn't?
I have piped a line in bash script and want to check if the pipe has data, before feeding it to a program.
Searching I found about test -t 0 but it doesn't work here. Always returns false.
So how to be sure that the pipe has data?
Example:
echo…
zetah
- 2,057
96
votes
3 answers
What does the letter 'u' mean in /dev/urandom?
I understand that reads to /dev/random may block, while reading /dev/urandom is guaranteed not to block.
Where does the letter u come into this? What does it signify?
Userspace? Unblocking? Micro?
Update:
Based on the initial wording of the…
Tom Hale
- 30,455
96
votes
5 answers
How do I recursively delete directories with wildcard?
I am working through SSH on a WD My Book World Edition. Basically I would like to start at a particular directory level, and recursively remove all sub-directories matching .Apple*. How would I go about that?
I tried
rm -rf .Apple* and rm -fR…
codedog
- 1,063
96
votes
7 answers
Why do hard links exist?
I know what hard links are, but why would I use them? What is the utility of a hard link?
Luc M
- 4,095
- 5
- 30
- 29
96
votes
2 answers
Why is nullglob not default?
In most shells nullglob isn't the default. That means, for example, if you run this command
ls *
in an empty directory, it will expand the * glob to a literal *, instead to an empty list of arguments. There are ways to change that behaviour, so…
Dakkaron
- 2,047
96
votes
6 answers
Understanding UNIX permissions and file types
I've never really got how chmod worked up until today. I followed a tutorial that explained a big deal to me.
For example, I've read that you've got three different permission groups:
owner (u)
group (g)
everyone (o)
Based on these three groups,…
Peter
- 1,031
96
votes
2 answers
Easy command line method to determine specific ARM architecture string?
I'm trying to write a script which will determine actions based on the architecture of the machine. I already use uname -m to gather the architecture line, however I do not know how many ARM architectures there are, nor do I know whether one is…
Thomas Ward
- 2,698