UNIX for Dummies Questions & Answers

It's also the single quotes as well as the \\ that's makes it work. Since I started off as a programmer before becoming an admin, I typically use double quotes everywhere (I also use $i for my temporary loop variables). The "Learning The Korn Shell" book advises using single quotes everywhere and using double quotes when you have variables within text strings or have to maintain formatting.

So my habit of using double quotes even with the double escape results in:

Code:

$ awk -F"\\$%" '{print $1}' files
asd$%fdsasa$%fdafas$%fdsa$%
asd$%fdsasa$%fdafas$%fdsa$%
asd$%fdsasa$%fdafas$%fdsa$%
asd$%fdsasa$%fdafas$%fdsa$%
asd$%fdsasa$%fdafas$%fdsa$%
asd$%fdsasa$%fdafas$%fdsa$%
asd$%fdsasa$%fdafas$%fdsa$%

But if you habitually use single quotes, you'd get the correct answer:

Code:

$ awk -F'\\$%' '{print $1}' files
asd
asd
asd
asd
asd
asd
asd

Thanks for that bit of information.

Carl

Code:

[sayonm@zion ~]$ sed -e 's/\$%/ /g' file | awk '{print $2}'
fdsasa
fdsasa
fdsasa
fdsasa
fdsasa
fdsasa
fdsasa

i think this can also be done....it just an alternative of cut, tr etc....the above mentioned methods are equally good

While converting the $% into ' ' or ':' or any other single character sounds good for this specific test data file, what if the file looked more like this:

asd$%rqe fd$%BAE:RWD$%fdjk$%jkas$ %fd$%jkfds
asd$%rqe fd$%BAE:RWD$%fdjk$%jkas$ %fd$%jkfds
asd$%rqe fd$%BAE:RWD$%fdjk$%jkas$ %fd$%jkfds
asd$%rqe fd$%BAE:RWD$%fdjk$%jkas$ %fd$%jkfds
asd$%rqe fd$%BAE:RWD$%fdjk$%jkas$ %fd$%jkfds
asd$%rqe fd$%BAE:RWD$%fdjk$%jkas$ %fd$%jkfds
asd$%rqe fd$%BAE:RWD$%fdjk$%jkas$ %fd$%jkfds
asd$%rqe fd$%BAE:RWD$%fdjk$%jkas$ %fd$%jkfds
asd$%rqe fd$%BAE:RWD$%fdjk$%jkas$ %fd$%jkfds

You can use the sed or tr commands to convert the $% into another character but if you don't know what's actually in the data file, doing this can be dangerous.

The best way is using a tool that'll let you define multi-character delimiters like awk, perl or python.

Carl