Pipes truncating data in cygwin from main and cygwin-3_4-branch

[キャロウ マーク]

> On Aug 15, 2023, at 9:30, Takashi Yano <takashi.yano@nifty.ne.jp> wrote:
> 
> Your test case does not work in command prompt as well.
> 
> Try
> type testfile | test-pipe sizeoftestfile
> in command prompt. It will fail.

Interesting.

> 
> New pipe implementation since cygwin 3.4.x provides the pipes
> more similar to pipe in command prompt for non-cygwin apps.

What are the differences between these pipes? What changed?

> 
> Since your test case is compiled with cl.exe, it is non-cygwin
> apps.

When the failure first appeared the bash shell included with Git for Windows was being used to run the pipe (`bash -c "cat foo | bar”`). The shell was started by ctest which had been run from PowerShell. Is this cygwin or non-cygwin?

in https://github.com/git-for-windows/git/issues/4464#issuecomment-1671137446 the author provided minimal adaption to the reproducer to compile it with g++ and reproduced the failure on Cygwin. It looks like the failure happens for both cygwin and non-cygwin. It is probably related to the new pipe implementation you mentioned.

Regards

    -Mark
-------------- next part --------------
A non-text attachment was scrubbed...
Name: signature.asc
Type: application/pgp-signature
Size: 528 bytes
Desc: Message signed with OpenPGP
URL: <https://cygwin.com/pipermail/cygwin/attachments/20230815/929691ca/attachment.sig>