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QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
Utilities & Libraries
C Library Reference
T
tcischars()
Determine the number of characters waiting to be read

QNX Momentics IDE User's Guide
This User's Guide describes version 8.0 of the Integrated Development Environment (IDE) that's part of the QNX Tool Suite.
QNX Software Development Platform
QNX SDP is a cross-compiling and debugging environment, including an IDE and command-line tools, for building binary images and programs for target boards running the QNX OS 8.0.
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        Determine the number of characters waiting to be read
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        Get time-accounting information
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        Time-specification structure
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        Process trace data
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        The abbreviations for the time zone for standard and daylight savings time
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tcischars()

QNX SDP8.0C Library ReferenceAPIDeveloper

Determine the number of characters waiting to be read

Synopsis:

#include <termios.h>

int tcischars( int filedes );

Arguments:

filedes: A file descriptor that's associated with the device that you want to check.

Library:

libc

Use the -l c option to qcc to link against this library. This library is usually included automatically.

Description:

The tcischars() function checks to see how many characters are waiting to be read from the given file descriptor, filedes.

Returns:

The number of characters waiting to be read, or -1 if an error occurred.

Errors:

ENOTTY: The filedes argument isn't the file descriptor for a character device.

Classification:

QNX OS


Safety:
Cancellation point	No
Signal handler	Yes
Thread	Yes

Page updated: August 09, 2024