select's FD_ISSET returns true with no data to read
Affects | Status | Importance | Assigned to | Milestone | |
---|---|---|---|---|---|
linux (Ubuntu) |
Confirmed
|
Undecided
|
Unassigned |
Bug Description
Description: Ubuntu 14.04.3 LTS
Release: 14.04
Ubuntu 3.13.0-
3.13.0-63-generic seems to work fine, but in 3.13.0-65-generic, when using select; FD_ISSET returns true even when there is no data on a tty with min=0, time=0. getchar() returns -1
Wondering if it's anything to do with the fix for https:/
Actually noticed this within sox:
play xx.wav
hangs due to continually reading the tty (it's not great code - but it showed up the bug). Whereas:
play xx.wav < /dev/null
is fine.
Cheers,
Tarim
---
ApportVersion: 2.14.1-0ubuntu3.15
Architecture: i386
AudioDevicesInUse:
USER PID ACCESS COMMAND
/dev/snd/
CurrentDesktop: Unity
DistroRelease: Ubuntu 14.04
HibernationDevice: RESUME=
InstallationDate: Installed on 2010-07-17 (1903 days ago)
InstallationMedia: Ubuntu 10.04 LTS "Lucid Lynx" - Release i386 (20100429)
IwConfig:
lo no wireless extensions.
eth0 no wireless extensions.
Lsusb:
Bus 002 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 004 Device 002: ID 1c4f:0034 SiGma Micro
Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub
Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub
MachineType: MICRO-STAR INTERNATIONAL CO.,LTD MS-7530
Package: linux (not installed)
ProcFB: 0 nouveaufb
ProcKernelCmdLine: BOOT_IMAGE=
ProcVersionSign
RelatedPackageV
linux-
linux-
linux-firmware 1.127.15
RfKill:
Tags: trusty
Uname: Linux 3.13.0-65-generic i686
UpgradeStatus: Upgraded to trusty on 2014-11-28 (308 days ago)
UserGroups: adm admin audio cdrom dialout lp lpadmin plugdev sambashare video www-data
_MarkForUpload: True
dmi.bios.date: 03/04/2009
dmi.bios.vendor: American Megatrends Inc.
dmi.bios.version: V1.2
dmi.board.
dmi.board.name: P7NGM-Digital (MS-7530)
dmi.board.vendor: MICRO-STAR INTERNATIONAL CO.,LTD
dmi.board.version: 1.0
dmi.chassis.
dmi.chassis.type: 3
dmi.chassis.vendor: MICRO-STAR INTERNATIONAL CO.,LTD
dmi.chassis.
dmi.modalias: dmi:bvnAmerican
dmi.product.name: MS-7530
dmi.product.
dmi.sys.vendor: MICRO-STAR INTERNATIONAL CO.,LTD
This bug is missing log files that will aid in diagnosing the problem. From a terminal window please run:
apport-collect 1502168
and then change the status of the bug to 'Confirmed'.
If, due to the nature of the issue you have encountered, you are unable to run this command, please add a comment stating that fact and change the bug status to 'Confirmed'.
This change has been made by an automated script, maintained by the Ubuntu Kernel Team.