Bash – How to detect dos format files in git bash

bashgrepnewlines

Git Bash is a nice bash shell you get in Windows as part of the installation of Git. It comes with other typical unix tools bundled inside, such as grep, sed, awk, perl. It doesn't have the file command.

In this shell, I want to detect files that have DOS-style line endings. I thought this command would work but it doesn't:

grep -l ^M$ *

It doesn't work, even files that don't have CR line endings match. For example if I create 2 sample files hello.unix and hello.dos, I can confirm with wc that hello.unix has 6 characters and hello.dos has 7 characters because of the extra CR, but both files match with grep. That is:

$ cat hello.*
hello
hello

$ wc hello.*
      1       1       7 hello.dos
      1       1       6 hello.unix
      2       2      13 total

$ grep -l ^M hello.*
hello.dos
hello.unix

Is this a bug in the implementation of grep in Git Bash?
Is there another way to find all files with DOS-style line endings?

Best Answer

EDIT: Silly me. Of course ^M is CR; and your command should work (works on my system). However, you need to type Ctrl-V Ctrl-M to get the literal '\r'/CR (and not two characters, ^ and M).

Alternatives:

Do this:

find dir -type f -print0 | xargs -0 grep -l `printf '\r\n'`

Or this:

find dir -type f -print0 | xargs -0 grep -lP '\r\n'

You can also use the file utility (not sure if it comes with GIT bash):

find dir -type f -print0 | xargs -0 file | grep CRLF

Related Solutions

Bash – way to get actual (uninterpreted) shell arguments in a function or script

The uninterpreted shell arguments are $1, $2, etc. You need to put their expansion in double quotes in most contexts, to avoid the value of the parameter being expanded further. "$@" gives you the list of all parameters.

For example, if you want to pass an argument of the shell script to your function, call it like this:

first_argument_as_filename_in_unix_syntax=$(posix "$1")

The double quotes are necessary. If you write posix $1, then what you're passing is not the value of the first parameter but the result of performing word splitting and globbing on the value of the first parameter. You will need to use proper quoting when calling the script, too. For example, if you write this in bash:

myscript c:\path with spaces\somefile

then the actual, uninterpreted arguments to myscript will be c:path, with and spacessomefile. So don't do this.

Your posix function is wrong, again because it lacks double quotes around $1. Always put double quotes around variable and command substitutions: "$foo", "$(foo)". It's easier to remember this rule than the exceptions where you don't actually need the quotes.

echo does its own processing in some cases, and calling external processes is slow (especially on Windows). You can do the whole processing inside bash.

posix () {
  path="${1//\\//}"
  case "$path" in
    ?:*) drive="${p:0:1}"; drive="${drive,}"; p="/$drive/${p:2}";;
  esac
  printf %s "$p"
}

_{The zsh feature that jw013 alluded to doesn't do what you seem to think it does. You can put noglob in front of a command, and zsh does not perform globbing (i.e. filename generation, i.e. expansion of wildcards) on the arguments. For example, in zsh, if you write noglob locate *foo*bar*, then locate is called with the argument *foo*bar*. You'd typically hide the noglob builtin behind an alias. This feature is irrelevant for what you're trying to do.}

Grep Command – Display Filename Once with Context and Line Numbers

I would change a few things about.

find_code() { 
    # assign all arguments (not just the first ${1}) to MATCH
    # so find_code can be used with multiple arguments:
    #    find_code errorCode
    #    find_code = 1111
    #    find_code errorCode = 1111
    MATCH="$@" 

    # For each file that has a match in it (note I use `-l` to get just the file name
    # that matches, and not the display of the matching part) I.e we get an output of:
    #
    #       srcdir/matching_file.c
    # NOT:
    #       srcdir/matching_file.c:       errorCode = 1111
    #
    grep -lr "$MATCH" ${SRCDIR} | while read file 
    do 
        # echo the filename
        echo ${file}
        # and grep the match in that file (this time using `-h` to suppress the 
        # display of the filename that actually matched, and `-n` to display the 
        # line numbers)
        grep -nh -A5 -B5 "$MATCH" "${file}"
    done 
}

Best Answer

Related Solutions

Bash – way to get *actual* (uninterpreted) shell arguments in a function or script

Grep Command – Display Filename Once with Context and Line Numbers

Related Question

Bash – way to get actual (uninterpreted) shell arguments in a function or script