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cannot open /dev/ttyq

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Applicable Environment

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Topic: cannot open /dev/ttyq
SDP: 6.4.0, 6.4.1, 6.5.0
Target: Any supported target

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Recommendation

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In QNX 6.3.2 I can look at the property of /dev/ttyq* device with the stty utility, for example:
# stty </ dev / ttyqb

But in 6.4.1 and 6.5, the same utility does not display anything. If I kill it, for example by pressing <Ctrl> <C>, then the following message appears:
sh: cannot open /dev/ttyqb: Interrupted function call

All tty* have the same behavior, except for those used in a photon at a terminal window.
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For Posix compliance an open of the slave pty device shall block until the master device is opened...this is what you are seeing. This was added in 640. (Try opening the master and your stty against the slave should complete, or try doing the stty against a tty device that is already opened via a pterm or telnet session.

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NOTE: This entry has been validated against the SDP version listed above. Use caution when considering this advice for any other SDP version. For supported releases, please reach out to QNX Technical Support if you have any questions/concerns.

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