I'm beginner in Bash Scripting and I need to assign to a variable a custom command output,not the entire command just a part of it.Is there a way I can do that?
The command:
gtf 1600 720 60
The Output:
# 1600x720 @ 60.00 Hz (GTF) hsync: 44.76 kHz; pclk: 93.10 MHz
Modeline "1600x720_60.00" 93.10 1600 1672 1840 2080 720 721 724 746 -HSync +Vsync
What I want to store:
"1600x720_60.00" 93.10 1600 1672 1840 2080 720 721 724 746 -HSync +Vsync
You can enclose your command in backticks to store its output:
a=`echo Hello`
Alternatively, you can also use $():
a=$(echo Hello)
If you want to store only a part of the output, you can pipe the output of your command to a postprocessing script, e.g. sed:
a=$(echo foo | sed 's/foo/bar/')
There are many ways to arrive at your desired output, but I like grep:
gtf 1600 720 60 | grep -Po '(Modeline)\K(.*)'
Here you would be using a regular expression with grep to capture any output on a line that follows "Modeline".
Then you can use command substitution to store the output in a variable:
OUTPUT=$(gtf 1600 720 60 | grep -Po '(Modeline)\K(.*)')
echo "$OUTPUT"
# "1600x720_60.00" 93.10 1600 1672 1840 2080 720 721 724 746 -HSync +Vsync
|) to the sed command, e.g.your_command | sed 's/^.*Modeline //'If the command writes the output tostderr, be sure to redirect first:your_command 2>&1