Summary: | Please add old Palm OS devices to udev blacklist | ||
---|---|---|---|
Product: | ModemManager | Reporter: | Lincoln Roop <lroop> |
Component: | general | Assignee: | ModemManager bug user <modemmanager> |
Status: | RESOLVED FIXED | QA Contact: | |
Severity: | normal | ||
Priority: | medium | CC: | noloader |
Version: | unspecified | ||
Hardware: | All | ||
OS: | All | ||
Whiteboard: | |||
i915 platform: | i915 features: |
Description
Lincoln Roop
2015-06-19 18:48:47 UTC
Pushed fix to git master and mm-1-4. I'm not sure how helpful this will be in general, but in my C program: int modem = open(device_path, O_RDWR | O_NOCTTY | O_SYNC); ... int res = ioctl(fd, TIOCEXCL, NULL); ... TIOCEXCL puts the file descriptor into exclusive mode, and it stops other programs from opening the device and mucking with state. The downside is it suffers a race. I think the ultimate fix is have the kernel honor O_EXCL on character devices and honor exclusive semantics. The kernel folks say no one has submitted a patch to make O_EXCL work as expected by typical user. I'm not sure what the shell folks will do if they have O_EXCL and use two shells to control the modem. But they will have what they need to stop the problem, so I guess they can figure it out. Having the kernel provide exclusive semantics for O_EXCL seems very natural to me. There's no sense in introducing a new flag like they did with sockets and SOCK_NONBLOCK. |
Use of freedesktop.org services, including Bugzilla, is subject to our Code of Conduct. How we collect and use information is described in our Privacy Policy.