rdchk()

Check to see if a read is likely to succeed

Synopsis:

#include <unix.h>

int rdchk( int fd );

Arguments:

fd

The file descriptor 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.

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This function is in libc.a, but not in libc.so (in order to save space).

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Description:

The rdchk() function checks to see if a read from the file descriptor, fd, is likely to succeed.

Returns:

The number of characters waiting to be read, or -1 if an error occurred (errno is set).

Errors:

ENOTTY

The fd argument isn't the file descriptor for a character device.

Classification:

Unix

See also:

tcischars()