Why does grep matches all the lines no matter what the pattern

Question

I'm having a problem using grep. I have a file http://pastebin.com/HxAcciCa that I want to check for certain patterns. And when I"m trying to search for it grep returns all the lines provided that the pattern already exists in the given file.

To explain more this is the code that I'm running

grep -F  "ENVIRO" "$file_pos" >> blah    

No matter what else I try even if I provide a whole line as a pattern bash always returns all the lines.
These are variations of what I'm trying:

grep -F  "E20" "$file_pos" >> blah
grep E20 "$file_pos" >> blah 
grep C:\E20-II\ENVIRO\SSNHapACS480.dll "$file_pos" >> blah
grep -F C:\E20-II\ENVIRO\SSNHapACS480.dll "$file_pos" >> blah

Also for some strange reasons when adding the -x option to grep, it doesn't return any line despite the fact that the exact pattern exists.

I've searched the web and the bash documentation for the cause but couldn't find anything.

My final test was the following

grep -F -C 1  "E20" "$store_pos" >> blah #store_pos has the same value as $file_pos

I thought maybe it was printing the lines after the result but that was not the case. I was using the blah file to see the output. Also I'm using Linux mint rebecca. Finally although the naming is quite familiar this question is not similiar to Why does grep match all lines for the pattern "\'"

And finally I would like to say that I am new to bash. I suspect The error might be due to the main file http://pastebin.com/HxAcciCa rather than the code?

Answer 1

From the comments, it appears that the file has carriage returns delimiting the lines, rather than the linefeeds that grep expects; as a result, grep sees the file as one huge line, that either matches or fails to match as a whole.

(Note: there are at least three different conventions about how to delimit the lines in a "plain text" file -- unix uses newline (\n), DOS/Windows uses carriage return followed by newline (\r\n), and pre-OSX versions of MacOS used just carriage return (\r).)

I'm not clear on how your file wound up in this format, but you can fix it easily with:

tr '\r' '\n' <badfile >goodfile

or on the fly with:

tr '\r' '\n' <badfile | grep ...