Find and remove DOS line endings on Ubuntu

Question

I have found that many of my files have DOS line endings. In VI they look like this: \"^M\". I don\'t want to modify files that don\'t have these DOS line endings. How do

Answer 1

Note if you're converting multi-byte files you need to take extra care, and should probably try to use the correct iconv or recode from-encoding specifications.

If it's a plain ASCII file, both of the below methods would work.

The flip program, in Debian the package is also called flip, can handle line-endings. From the manual:

When asked to convert a file to the same format that  it already 
has, flip  causes  no change to the file. Thus to convert all
files to **IX format you can type

flip -u *

and all files will end up right, regardless of whether they were 
in MS-DOS or in **IX format to begin with. This also works in the
opposite direction.

Or you could use GNU recode:

< /etc/passwd recode ..pc | tee a b > /dev/null
file a b

Output:

a: ASCII text, with CRLF line terminators
b: ASCII text, with CRLF line terminators

Convert to unix line-endings:

recode pc.. a b
file a b

Output:

a: ASCII text
b: ASCII text

recode abbreviates dos line-endings as pc, so the logic with pc.. is: convert from pc format to the default, which is latin1 with unix line-endings.