ptsname man page


This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the corresponding Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux.

ptsname — get name of the slave pseudo-terminal device


#include <stdlib.h>

char *ptsname(int fildes);


The ptsname() function shall return the name of the slave pseudo-terminal device associated with a master pseudo-terminal device. The fildes argument is a file descriptor that refers to the master device. The ptsname() function shall return a pointer to a string containing the pathname of the corresponding slave device.

The ptsname() function need not be thread-safe.

Return Value

Upon successful completion, ptsname() shall return a pointer to a string which is the name of the pseudo-terminal slave device. Upon failure, ptsname() shall return a null pointer. This could occur if fildes is an invalid file descriptor or if the slave device name does not exist in the file system.

The application shall not modify the string returned. The returned pointer might be invalidated or the string content might be overwritten by a subsequent call to ptsname().


No errors are defined.

The following sections are informative.


See the Rationale section for posix_openpt().

See Also

grantpt(), open(), posix_openpt(), ttyname(), unlockpt()

The Base Definitions volume of POSIX.1‐2008, <stdlib.h>