Assigning the output of a command to a variable

bash unix sh
user3114665 picture user3114665 · Dec 19, 2013 · Viewed 135.2k times · Source

I am new with unix and I am writing a shell script.

When I run this line on the command prompt, it prints the total count of the number of processes which matches:

ps -ef | awk '/siebsvc –s siebsrvr/ && !/awk/ { a++ } END { print a }'

example, the output of the above line is 2 in the command prompt.

I want to write a shell script in which the output of the above line (2) is assigned to a variable, which will be later be used for comparison in an if statement.

I am looking for something like

output= `ps -ef | awk '/siebsvc –s siebsrvr/ && !/awk/ { a++ } END { print a }'`
echo $output

But when i run it, it says output could not be found whereas I am expecting 2. Please help.

Answer

Marutha picture Marutha · Dec 19, 2013

You can use a $ sign like: 

OUTPUT=$(expression)

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