ttyname()
QNX SDP8.0C Library ReferenceAPIDeveloper
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:
| Safety: | |
|---|---|
| Cancellation point | No | 
| Signal handler | No | 
| Thread | No | 
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