Re: [PATCH] retry opening startup files on EINTR

[Chet Ramey]

On 2/20/24 11:37 AM, Grisha Levit wrote:
> On Tue, Feb 20, 2024 at 9:18 AM Chet Ramey <chet.ramey@case.edu> wrote:
> > Well, depending on when the terminal emulator sends the SIGWINCH, this is
> > probably a bug in Dropbox or the File Provider code. Bash installs its
> > SIGWINCH handler with SA_RESTART, and the default disposition is to
> > discard, so even if a SIGWINCH arrives before bash installs its handler it
> > should not interrupt open().
> >
> > I suppose we'll have to work around it.
>
> sigaction(2) says:
>
>      The affected system calls include open(2), read(2), write(2),
>      sendto(2), recvfrom(2), sendmsg(2) and recvmsg(2) on a communications
>      channel or a slow device (such as a terminal, but not a regular file)
>
> so I guess a SIGWINCH during the open(2) for ~/.bash_profile, etc. can
> still get interrupted.

I went by POSIX:

"This flag affects the behavior of interruptible functions; that is, those
specified to fail with errno set to [EINTR]. If set, and a function
specified as interruptible is interrupted by this signal, the function 
shall restart and shall not fail with [EINTR] unless otherwise specified."

and POSIX does not otherwise specify for open. But I guess the macOS man
page falls under the "otherwise specified" part.

Still have to work around it.

--
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, UTech, CWRU    chet@case.edu    http://tiswww.cwru.edu/~chet/