If you know that you want all of the lines in a given file from n to EOF the following is the sed command:
sed -n '3,$p' some_file.txtTo print out lines 2 – 5 simply modify it to:
sed -n '2,5p' some_file.txtCategory: Linux
Removing the Last Token From a String in Bash with awk
Let’s say that you have some number of files for which you want to create a containing directory that is named with all but the last token of the file name, and you want to remove just the last token to create the name of the directory.
Much easier to explain with an example. Given this list of files:
ls -1
foo_10_10_sometrash
foo_1_sometrash
foo_2_sometrash
foo_3_sometrash
foo_4_sometrash
foo_5_5_sometrash
foo_5_sometrash
foo_6_6_sometrash
foo_7_7_sometrash
foo_8_8_sometrash
foo_9_9_sometrashYou want to create a directory for each → Continue reading “Removing the Last Token From a String in Bash with awk”
Removing The Last N Character From a String in Bash Script with sed
Here is a quick one-liner for trimming a specific number of characters from the end of a string under bash:
# Remove the last 5 characters
$ echo "somestringwith12345" | sed "s/.....$//g"
$ somestringwith
# Remove the last 3 characters
$ echo "somestringwith12345" | sed "s/...$//g"
$ somestringwith12Count The Number of Characters In a Field With awk
A quick one-liner for counting the number of characters in a given field for each line in an ASCII file.
for i in `cat source.txt`; do echo $i | awk {'print length($1)}' >> counts.txtRestarting XServer in Fedora 20
I was having problems logging in this morning to my laptop. When I entered my password, it just hung. I pressed Ctrl-f2 to switch to an alternate tty, logged in as root and checked for errors in /var/log/messages.
Not seeing anything, I figured, I’d try and restart the Xserver. Still not being completely familiar with the sysctl paradigm it wasn’t obvious how to restart it.
So, as root, I simply switched the runlevel to 3, and then back to 5 → Continue reading “Restarting XServer in Fedora 20”
Creating a Beep from a Command Line or Shell Script
If you have a long-running command on shell-script that you want to generate a beep upon completion on your PC running Linux do the following:
Make sure that the pcspkr module is loaded:
# modprobe pcspkrThen create a wrapper shell script that looks something like this:
#!/bin/bash
# Some long running command here . . .
echo -e '\a' /dev/consoleDisabling Window Snapping for Fedora Core 20 Under Xfce
For me, window snapping is incredibly annoying.
For FC 20 with the Xfce spin, there a couple of knobs to turn before it can be turned off completely:
Applications Menu/Settings/Window Manager:
Go to the Advanced tab and uncheck ‘Snap windows to screen border’ and ‘Snap windows to other windows’
Applications Menu/Settings/Window Manager Tweaks:
Go to Accessibility tabUncheck the ‘Use edge resistance instead of window snapping’→ Continue reading “Disabling Window Snapping for Fedora Core 20 Under Xfce”