ptsname(3) - NetBSD Manual Pages

Command: Section: Arch: Collection:  
PTSNAME(3)              NetBSD Library Functions Manual             PTSNAME(3)


NAME
ptsname, ptsname_r -- get the pathname of the slave pseudo-terminal device
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <stdlib.h> char * ptsname(int masterfd); int ptsname_r(int masterfd, char *buf, size_t buflen);
DESCRIPTION
The ptsname() function returns the pathname of the slave pseudo-terminal device that corresponds to the master pseudo-terminal device associated with masterfd. The ptsname() function is not reentrant or thread-safe. The ptsname_r() function places the pathname of the slave pseudo-terminal device that corresponds to the master pseudo-terminal device associated with masterfd int the buf argument copying up to buflen characters. The buf is always NUL terminated.
RETURN VALUES
If successful, ptsname() returns a pointer to a nul-terminated string containing the pathname of the slave pseudo-terminal device. If an error occurs ptsname() will return NULL and errno is set to indicate the error. If successful, ptsname_r() places a nul-terminated string containing the pathname of the slave pseudo-terminal device in buf and returns 0. If an error occurs ptsname_r() will return an error number indicating what went wrong.
ERRORS
The ptsname() and ptsname_r() functions will fail if: [EACCESS] the corresponding pseudo-terminal device could not be accessed. [EBADF] masterfd is not a valid descriptor. [EINVAL] masterfd is not associated with a master pseudo-termi- nal device. In addition the ptsname_r() function will return: [EINVAL] the buf argument is NULL. [ERANGE] the name of the pseudo-terminal is longer than bufsiz characters plus the terminating NUL.
NOTES
The error returns of ptsname() are a NetBSD extension. The ptsname() function is equivalent to: struct ptmget pm; return ioctl(masterfd, TIOCPTSNAME, &pm) == -1 ? NULL : pm.sn; Both the ptsname() and ptsname_r() functions will also return the name of the slave pseudo-terminal if a file descriptor to the slave pseudo-termi- nal is passed to masterfd. This is a convenient extension because it allows one to use the file descriptor obtained by open(2) /dev/tty to obtain the name of the pseudo- terminal for the current process.
SEE ALSO
ioctl(2), open(2), grantpt(3), posix_openpt(3), unlockpt(3)
STANDARDS
The ptsname() function conforms to IEEE Std 1003.1-2001 (``POSIX.1''). Its first release was in X/Open Portability Guide Issue 4, Version 2 (``XPG4.2''). NetBSD 9.1 February 7, 2018 NetBSD 9.1
Powered by man-cgi (2021-06-01). Maintained for NetBSD by Kimmo Suominen. Based on man-cgi by Panagiotis Christias.