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Re: 1.7.8: write fails with EAGAIN

On 3/9/2011 1:24 PM, Robert Wruck wrote:

Hang on, you are saying that a *blocking* write(2) to a pipe returns
with EAGAIN? Are you sure? It would be quite a surprise if git would
actually do that. EAGAIN is only an expected error for non-blocking
I/O, so applications which use blocking I/O usually only test for EINTR.

I checked out the winsup sources and built a cygwin1.dll for debugging (btw: Could you update the FAQ to state that gcc4 is required instead of gcc?).

What I found out:

In, write_overlapped, there is the call to WriteFile:

bool res = WriteFile (get_output_handle (), ptr, len, &nbytes, get_overlapped

Surprisingly, this returns FALSE / nbytes = 0 / GetLastError =
ERROR_INVALID_HANDLE on WinXP if the number of bytes exceeds some maximum and
 the handle refers to a pipe. Since you don't know what kind of handle you're
writing to in write_overlapped, it seems reasonable to do the write in




A: Yes.
Q: Are you sure?
A: Because it reverses the logical flow of conversation.
Q: Why is top posting annoying in email?

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