Cat and Sed Command Help.
 

I need to know something about the cat command.

Lets say i have a text file named test.tct

It contains
ABC A 123
ABC A 456
ABC A 789
HET A 123
HET A 123
HET A 567
ABC A 123
ABC A 565
ABC A 123
TER
ABC B 123
ABC B 456
ABC B 789
HET B 123
HET B 123
HET B 567
ABC B 123
ABC B 565
ABC B 123
TER
HET 123
HET 123
HET 678

Is there a way for linux to print all the lines between ABC A and TER(Lines 1-10) ?
The file is dynaminc, some files might have a 100 lines and some might have just 5. so head -n 5 doesnt work. Let me know if you know some command.

Hi,

Using sed is one way:

sed -n '1,10p' infile

The -n turns of normal printing of lines,
'1,10p' prints (p) lines 1 to 10 (or up to as many as ten).

Hope this helps.

The thing is I dont know the line numbers. All i know is the First 6 characters of my string are "ABC A" and the script should stop read when it hits TER

Hi,

Maybe this will help. It's the same command, but using regexp to determine the line numbers:

sed -n '/ABC A/,/TER/p' infile

If the input given in your first post is used, the following is the output:

ABC A 123
ABC A 456
ABC A 789
HET A 123
HET A 123
HET A 567
ABC A 123
ABC A 565
ABC A 123
TER

Hope this works for you.

Thanks a lot! You helped me out a lot!

One small question.
is it possible to make sed read the lines only if its starts with ABC?
like
sed -n ^'/ABC A/,/TER/p' infile
that doesnt work... what do i do?

You could put grep in front of it....

SED Command in Linux
 

I have a huge text file in Linux. I use Cat to view the output. my command is

cat file.txt sed -n ^"/.....................A/,/TER/p"

It should read the file for a string starting with ".....................A" where . can be any character and it should stop with TER.

This outputs "sed: -e expression #1, char 1: unknown command: `^'"

whats wrong?

It doesnt work... It outputs all the lines in the file... what do i do now?

Shouldn't you be using "grep" to do this..?

can you use grep to get information between 2 lines in the file? i dint know you can...

If this is from the same example you were using yesterday, here is another way using sed.

Its from the same example... but bit modified

Here the textfile
So it must start reading ".....................A" and end at TER.

How do i do that?

How about this?

returns p event not found...

isnt there an easy way to read all the information between 2 lines?

Like
cat text.txt |grep ^".....................A","TER" ?

the sed command would work if i defined to read the file only if it starts with ".....................A"