patch command incorrectly capitalizes filenames that live on external USB flash drives

[Thomas Wolff]

Am 28.04.2020 um 21:27 schrieb Jason Gross via Cygwin:
> Consider the following script in foo.sh:
> ```
> #!/usr/bin/env bash
>
> set -ex
>
> cd "$1"
> rm -rf foo
> mkdir foo
> cd foo
> cat > Makefile <<EOF
> a
> b
> c
> d
> e
> EOF
> cat > diff <<EOF
> diff --git a/Makefile b/Makefile
> index 9405325..86d2f8c 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -1,5 +1,5 @@
>   a
>   b
> -c
> +ccc
>   d
>   e
> EOF
> patch -p1 -i ./diff
> ls
> ```
>
> If I run `./foo.sh /cygdrive/c/`, I get, as expected,
> ```
> + cd /cygdrive/c/
> + rm -rf foo
> + mkdir foo
> + cd foo
> + cat
> + cat
> + patch -p1 -i ./diff
> patching file Makefile
> + ls
> diff  Makefile
> ```
>
> If I instead run `./foo.sh /cygdrive/h/`, I get
> ```
> + cd /cygdrive/h/
> + rm -rf foo
> + mkdir foo
> + cd foo
> + cat
> + cat
> + patch -p1 -i ./diff
> patching file Makefile
> + ls
> diff  MAKEFILE
> ```
You are throwing a puzzle into the mailing list and if you are lucky, 
someone may like to solve it.
But perhaps: can you try to minimize your test case, please.
Something like: touch Makefile; ls (if that's it).

> My C drive is an internal SSD (NTFS), my H drive is an external flash
> drive (FAT32).  I installed cygwin with the commands:
> ```
> powershell -Command "(New-Object
> Net.WebClient).DownloadFile('http://www.cygwin.com/setup-x86_64.exe',
> 'setup-x86_64.exe')"
> SET CYGMIRROR=http://mirror.easyname.at/cygwin
> SET CYGROOT=H:\cygwin64
> SET CYGCACHE=%CYGROOT%\var\cache\setup
> setup-x86_64.exe -qnNdO -R %CYGROOT% -l %CYGCACHE% -s %CYGMIRROR% -P
> rsync -P patch -P diffutils -P make -P unzip -P m4 -P findutils -P
> time -P wget -P curl -P git -P
> mingw64-x86_64-binutils,mingw64-x86_64-gcc-core,mingw64-x86_64-gcc-g++,mingw64-x86_64-pkg-config,mingw64-x86_64-windows_default_manifest
> -P mingw64-x86_64-headers,mingw64-x86_64-runtime,mingw64-x86_64-pthreads,mingw64-x86_64-zlib
> -P python3
> ```
>
> Running `patch -v` says `GNU patch 2.7.4`.  Note that this happens
> regardless of whether I install cygwin itself on my external flash
> drive or on my internal HD.
>
> This came up when trying to run `opam install findlib` (which fails
> when the home directory is on an external USB drive).
>
> -Jason
>