ttyname()

Get a fully qualified pathname for a file

Synopsis:

#include <unistd.h>

char *ttyname( int filedes );

Arguments:

filedes: A file descriptor that's associated with the file whose name you want to get.

Library:

libc

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

Description:

The ttyname() function returns a pointer to a static buffer that contains a fully qualified pathname associated with the file associated with filedes.

Returns:

A pointer to the pathname for filedes, or NULL if an error occurred (errno is set).

Errors:

EAGAIN: The device driver was in use by another process, or the driver was unable to carry out the request due to an outstanding command in progress.
EBADF: The filedes argument isn't a valid file descriptor.
EINTR: The function was interrupted by a signal.
ENOSYS: The ttyname() function isn't implemented for the filesystem specified by filedes.
ENOTTY: The filedes argument doesn't refer to a tty.
EPERM: The process doesn't have sufficient permission to carry out the requested command.

Examples:

/*
 * The following program prints out the name
 * of the terminal associated with stdin.
 */
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>

int main( void )
{
    if( isatty( 0 ) ) {
       printf( "%s\n", ttyname( 0 ) );
    } else {
       printf( "\n" );
    }
    return EXIT_SUCCESS;
}

Classification:

POSIX 1003.1

Safety:
Cancellation point	No
Interrupt handler	No
Signal handler	No
Thread	No