I am new in linux and AWK as well. I have a file in my home folder called testing.txt and i am trying to read the file using this awk command:
**arjun@arjun-Aspire-4741:~$ awk ´{print $1}´ testing.txt¨**
And I am getting this as output
**¨awk: ´{print
awk: ^ invalid char '�' in expression
arjun@arjun-Aspire-4741:~$ ¨**
The problem is that you've used forward ticks instead of quotes (in this case only single quotes are appropriate):
awk '{print $1}' testing.txt
instead of
awk ´{print $1}´ testing.txt
In shell, strings in double quotes " can contain expressions with special meaning (such as backticks, variables) which will be expanded before the string is processed as part of the full shell command. Strings in single quotes ' are fully escaped; to put it another way, the string is passed literally without any interpretation. That's why you should use single quotes when writing awk scripts, because the awk variable dereference operator $ is the same as in shell. There are no other valid string-delimiting characters*.
I initially thought you'd used backticks (thanks to Andras Deak for spotting my error).
Backticks have a special meaning in shell (equivalent to wrapping something in $(...)): execute this string as a command, and evaluate to its output (stdout). This is done before your main command is executed.
So, if I do
cat `echo myfile`
this turns into
cat myfile
which then executes.
You can read more about shell behaviour in a few places:
* ignoring that spaces are also technically string-delimiters
invalid char '�' instead of something about a token or a command not found.
