grep syntax issue on Lion

Question

I have a text file and looking for the single line bird. Using OS X Lion and grep 2.5.1.

this works:

grep '^bird' file.txt

but this doesn't

grep '^bird$' file.txt

There is not a blank space at the end of the line. What am I doing wrong?

thx

Answer 1

Its usually because of a DOS formatted text file (CRLF). To clean the file you can install a tooö like dos2unix; but usually works even simpler by using the tr tool:

tr -d '\r' < testfile > output.txt

Answer 2

I'm guessing it's a CRLF file (dos formatted text file)

[bob@erasmas tmp]$ cat testfile
bird
notbird
[bob@erasmas tmp]$ cat testfile.dos
bird
notbird
[bob@erasmas tmp]$ file testfile
testfile: ASCII text
[bob@erasmas tmp]$ file testfile.dos
testfile.dos: ASCII text, with CRLF line terminators
[bob@erasmas tmp]$ grep '^bird' testfile
bird
[bob@erasmas tmp]$ grep '^bird' testfile.dos
bird
[bob@erasmas tmp]$ grep '^bird$' testfile
bird
[bob@erasmas tmp]$ grep '^bird$' testfile.dos

Note: This was on a Linux machine, as this is not specific to OS X (if this is infact the problem).

Run "file" on file.txt and see if it has CRLF line endings.

Answer 3

If you want to keep the MS-DOS formatting, then you can insert the MS-DOS carriage return within the pattern. On linux I press CTRL-V CTRL-M to produce the literal ^M representing the MS-DOS CR (sometimes noted as \r). Hope on OS X you will find how to produce the literal CR.

grep --color=none "^bird^M$"