I want to put the output of command in bash variable and then further use that variable in other command
Suppose i want something like this
ls | $(variable) |awk '/$variable/{print "here"}'
-
1you need a better example problem. The current one doesn't make any sense. We really need to see 1. sample input, 2. required output, 3. actual output, 4. code that you've tried to solve a real problem. Good luck.shellter– shellter2013-02-01 04:15:20 +00:00Commented Feb 1, 2013 at 4:15
Add a comment
|
4 Answers
To put command output into variable you can use following format in bash
variable=`pwd`
echo $variable
Comments
You can try:
variable=$(ls); awk "/$variable/"'{print "here"}'
Note 1: /$variable/ is surrounded by double quotes, otherwise it won't be replaced by output of command.
Note 2: The above command may fail since the output of ls may contains "/" or newline, which will break the awk command. You may change ls to something like ls | tr '\n' ' ' | tr -d '/' | sed 's/ *$//g'(replace all newlines with spaces; delete all slashes; remove the trailing whitespace), depending on your goal.
Note 3: to avoid variable assignment polluting the current shell's environment, you can wrap the above command by parentheses, i.e. (variable=$(some_command); awk "/$variable/"'{print "here"}')
Comments
I don't know that you can easily do it in a single step like that, but I don't know why you'd pipe it to awk and use it in the script like that anyway. Here's the two step version, but I'm not really sure what it does:
variable=$(ls)
echo ${variable} | awk "/${variable}/{printf \"here\"}"
2 Comments
user2027303
Acutally i would like to do it in single line. is there any way
Carl Norum
Well, you could put a
;. Why does it need to be a single pipeline?Or
now=`date`
Back ticks
Which is easier for me since it works in any shell or perl
1 Comment
tripleee
Backticks are equivalent to modern
$(command substitution) syntax in the trivial case, but are less easy to use in the nontrivial case. The argument that they work in Perl too is a poor consolation when you run into complications. This syntax is obsolescent in the shell for a reason.