Unix and Linux Stack Exchange
Unix and Linux Stack Exchange

Most Popular

more tags
1500 questions
95
votes
3 answers

How do I recover from the Heartbleed bug in OpenSSL?

CVE-2014-0160 a.k.a. Heartbleed is a vulnerability in OpenSSL. It looks scary. How do I determine whether I am affected? If I'm affected, what do I need to do? Apparently upgrading isn't enough.
Gilles 'SO- stop being evil'
  • 807,993
  • 194
  • 1,674
  • 2,175
95
votes
13 answers

bash: test if $WORD is in set

I am looking for a construct in bash, to decide if a variable $WORD is one of defined words. I need something like this: if "$WORD" in dog cat horse ; then echo yes else echo no fi does bash have such construct? If not, what would be the…
Martin Vegter
  • 69
  • 66
  • 195
  • 326
95
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
  • 1,521
  • 1
  • 11
  • 7
94
votes
15 answers

Best way to search through shell's history

Is there a better way to search my history file for a command than grep? I do have some idea what the command starts as, but I don't know how far back in the history it is. update: was formerly zsh specific but due to overlapping answers feel free…
xenoterracide
  • 57,918
  • 74
  • 184
  • 250
94
votes
5 answers

Splitting string by the first occurrence of a delimiter

I have a string in the next format id;some text here with possible ; inside and want to split it to 2 strings by first occurrence of the ;. So, it should be: id and some text here with possible ; inside I know how to split the string (for instance,…
gakhov
  • 1,095
  • 2
  • 8
  • 9
94
votes
2 answers

How to display the Linux kernel command line parameters given for the current boot?

In the grub.conf configuration file I can specify command line parameters that the kernel will use, i.e.: kernel /boot/kernel-3-2-1-gentoo root=/dev/sda1 vga=791 After booting a given kernel, is there a way to display the command line parameters…
colemik
  • 1,361
  • 2
  • 11
  • 11
94
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
  • 2,269
  • 2
  • 9
  • 12
94
votes
6 answers

Create partition aligned using parted

I'm partitioning a non-SSD hard disk with parted because I want a GPT partition table. parted /dev/sda mklabel gpt Now, I'm trying to create the partitions correctly aligned so I use the following command to know where the first sector…
Marc
  • 1,651
  • 3
  • 14
  • 16
94
votes
3 answers

How to rsync multiple source folders

I want to rsync multiple sources and I wonder the best way to achieve that. e.g. /etc/fstab /home/user/download I thought about 3 solutions : Solution 1 multiple call to rsync rsync -a /etc/fstab bkp rsync -a /home/user/download bkp con : harder…
user1437346
  • 1,071
  • 1
  • 8
  • 5
94
votes
3 answers

Can sed save its output to a file?

> can do it. echo "text" > file tee can do it. echo "test" | tee file Can sed do it without using either of the above? Is it possible to save the output of a sed command to a file without using either > or tee?
Folaht
  • 962
  • 5
  • 21
  • 36
94
votes
3 answers

Awesome symbols and characters in a bash prompt

I just ran across a screenshot of someone's terminal: Is there a list of all of the characters which can be used in a Bash prompt, or can someone get me the character for the star and the right arrow?
Naftuli Kay
  • 38,686
  • 85
  • 220
  • 311
94
votes
2 answers

How to limit a process to one CPU core in Linux?

How to limit process to one cpu core ? Something similar to ulimit or cpulimit would be nice. (Just to ensure: I do NOT want to limit percentage usage or time of execution. I want to force app (with all it's children, processes (threads)) to use one…
Grzegorz Wierzowiecki
  • 13,865
  • 23
  • 89
  • 137
94
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
  • 4,025
  • 5
  • 30
  • 29
94
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
  • 1,011
  • 1
  • 10
  • 18
94
votes
14 answers

How to rsync files between two remotes?

I would like to transfer files between two remote hosts using on local shell, but it seems rsync doesn't support synchronisation if two remotes are specified as follow: $ rsync -vuar host1:/var/www host2:/var/www The source and destination cannot…
kenorb
  • 20,250
  • 14
  • 140
  • 164
1 2 3
…
99 100