findstr or grep that autodetects chararacter encoding (UTF-16)

问题

I want to do this:

 findstr /s /c:some-symbol *

or the grep equivalent

 grep -R some-symbol *

but I need the utility to autodetect files encoded in UTF-16 (and friends) and search them appropriately. My files even have the byte-ordering mark FFEE in them so I'm not even looking for heroic autodetection.

Any suggestions?

---

I'm referring to Windows Vista and XP.

回答1:

Thanks for the suggestions. I was referring to Windows Vista and XP.

I also discovered this workaround, using free Sysinternals strings.exe:

C:\> strings -s -b dir_tree_to_search | grep regexp 

Strings.exe extracts all of the strings it finds (from binaries, but works fine with text files too) and prepends each result with a filename and colon, so take that into account in the regexp (or use cut or another step in the pipeline). The -s makes it do a recursive extraction and -b just suppresses the banner message.

Ultimately I'm still kind of surprised that the flagship searching utilities Gnu grep and findstr don't handle Unicode character encodings natively.

回答2:

On Windows, you can also use find.exe.

find /i /n "YourSearchString" *.*

The only problem is this prints file names followed by matches. You may filter them by piping to findstr

find /i /n "YourSearchString" *.* | findstr /i "YourSearchString"

回答3:

A workaround is to convert your UTF-16 to ASCII or ANSI

TYPE UTF-16.txt > ASCII.txt

Then you can use FINDSTR.

FINDSTR object ASCII.txt

回答4:

findstr /s /c:some-symbol *

can be replaced with the following character encoding aware command:

for /r %f in (*) do @find /i /n "some-symbol" "%f"

回答5:

According to this blog article by Damon Cortesi grep doesn't work with UTF-16 files, as you found out. However, it presents this work-around:

for f in `find . -type f | xargs -I {} file {} | grep UTF-16 | cut -f1 -d\:`
        do iconv -f UTF-16 -t UTF-8 $f | grep -iH --label=$f ${GREP_FOR}
done

This is obviously for Unix, not sure what the equivalent on Windows would be. The author of that article also provides a shell-script to do the above that you can find on github here.

This only greps files that are UTF-16. You'd also grep your ASCII files the normal way.

回答6:

In higher versions of Windows, UTF-16 is supported out-of-box. If not, try changing active code page by chcp command.

In my case when using findstr alone was failing for UTF-16 files, however it worked with type:

type *.* | findstr /s /c:some-symbol

回答7:

You didn't say which platform you want to do this on.

On Windows, you could use PowerGREP, which automatically detects Unicode files that start with a byte order mark. (There's also an option to auto-detect files without a BOM. The auto-detection is very reliable for UTF-8, but limited for UTF-16.)

来源：https://stackoverflow.com/questions/408079/findstr-or-grep-that-autodetects-chararacter-encoding-utf-16