Most Popular
1500 questions
202
votes
5 answers
Is there any way to execute commands from history?
For example:
[root@ip-10-0-7-125 ~]# history | grep free
594 free -m
634 free -m | xargs | awk '{print "free/total memory" $17 " / " $ 8}'
635 free -m
636 free -m | xargs | awk '{print "free/total memory" $9 " / " $ 10}'
736 df -h |…
The One
- 4,862
202
votes
6 answers
Return only the portion of a line after a matching pattern
So pulling open a file with cat and then using grep to get matching lines only gets me so far when I am working with the particular log set that I am dealing with. It need a way to match lines to a pattern, but only to return the portion of the line…
MaQleod
- 2,614
202
votes
5 answers
How to choose directory name during untarring
Say I have a file named ugly_name.tar, which when extracted, becomes ugly_name directory. What command can I use so that the resulting directory name is pretty_name instead?
tshepang
- 65,642
201
votes
3 answers
What's the difference between a normal user and a system user?
Some documentation I'm going through has a boolean switch on whether or not a user is a 'system' user or a 'normal' user (defaulting to 'normal').
What is the difference between these two modes of user-ship? I don't need to learn what a user is or…
Sean Allred
- 2,489
201
votes
5 answers
How do I add X days to date and get new date?
I have Linux ( RH 5.3) machine
I need to add/calculate 10 days plus date so then I will get new date (expiration date))
for example
# date
Sun Sep 11 07:59:16 IST 2012
So I need to get
NEW_expration_DATE = Sun Sep 21 07:59:16 IST…
yael
200
votes
4 answers
How to combine 2 -name conditions in find?
I would like to search for files that would not match 2 -name conditions. I can do it like so :
find /media/d/ -type f -size +50M ! -name "*deb" ! -name "*vmdk"
and this will yield proper result but can I join these 2 condition with OR somehow ?
Patryk
- 14,096
200
votes
14 answers
How can I move files and view the progress (e.g. with a progress bar)?
When moving large directories using mv, is there a way to view the progress (%)?
The cp command on gentoo had a -g switch that showed the progress.
letronje
- 2,195
200
votes
14 answers
How to uncompress zlib data in UNIX?
I have created zlib-compressed data in Python, like this:
import zlib
s = '...'
z = zlib.compress(s)
with open('/tmp/data', 'w') as f:
f.write(z)
(or one-liner in shell: echo -n '...' | python2 -c 'import sys,zlib;…
mykhal
- 3,231
200
votes
3 answers
ifconfig command not found
I've just installed CentOS7 as a virtual machine on my mac (osx10.9.3 + virtualbox) .Running ifconfig returns command not found. Also running sudo /sbin/ifconfig returns commmand not found. I am root. The output of
echo $PATH is as below.…
RobSeg
- 2,450
200
votes
3 answers
Easily unpack DEB, edit postinst, and repack DEB
I'm attempting to install Intel's OpenCL SDK but the DEB files are buggy conversions from RPM (see here for the curious). I need to edit the postinst script in the DEB they provide.
How can I take an existing DEB, extract the contents (including…
John Jumper
- 2,105
199
votes
6 answers
Generate File of a certain size?
I'd like to generate a file with the name example.file. I could use
touch example.file
but I want the file to be exactly 24MB in size. I already checked the manpage of touch, but there is no parameter like this. Is there an easy way to generate…
R_User
- 2,093
- 2
- 13
- 5
198
votes
5 answers
Is there a way to redirect nohup output to a log file other than nohup.out?
I frequently use the program nohup so that my processes are immune to hangups. So if I want to make the program program immune to hangups, I use the command
nohup program &
where & puts the process in the background.
When starting, nohup gives me…
Andrew
- 16,855
198
votes
4 answers
Where do executables look for shared objects at runtime?
I understand how to define include shared objects at linking/compile time. However, I still wonder how do executables look for the shared object (*.so libraries) at execution time.
For instance, my app a.out calls functions defined in the lib.so…
rahmu
- 20,023
198
votes
6 answers
How do I grep recursively through .gz files?
I am using a script to regularly download my gmail messages that compresses the raw .eml into .gz files. The script creates a folder for each day, and then compresses every message into its own file.
I would like a way to search through this archive…
Kendor
- 2,081
197
votes
6 answers
What are the pros/cons of Upstart and systemd?
It appears systemd is the hot new init system on the block, same as Upstart was a few years ago. What are the pros/cons for each? Also, how does each compare to other init systems?
tshepang
- 65,642