2 .\" Copyright (c) 1996 Joerg Wunsch
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26 .\" $FreeBSD: src/lib/libutil/pty.3,v 1.8.2.3 2001/12/17 10:08:32 ru Exp $
34 .Nd auxiliary functions to obtain a pseudo-terminal
43 .Fn openpty "int *amaster" "int *aslave" "char *name" "struct termios *termp" "struct winsize *winp"
45 .Fn forkpty "int *amaster" "char *name" "struct termios *termp" "struct winsize *winp"
49 attempts to obtain the next available pseudo-terminal from the system (see
51 If it successfully finds one, it subsequently tries to change the
52 ownership of the slave device to the real UID of the current process,
53 the group membership to the group
55 (if such a group exists in the system), the access permissions for
56 reading and writing by the owner, and for writing by the group, and to
57 invalidate any current use of the line by calling
65 copies the pathname of the slave pty to this area. The caller is
66 responsible for allocating the required space in this array.
75 initializes the termios and window size settings from the structures
76 these arguments point to, respectively.
78 Upon return, the open file descriptors for the master and slave side
79 of the pty are returned in the locations pointed to by
88 to obtain the next available pseudo-terminal from the system. Upon success,
89 it forks off a new process. In the child process, it closes the descriptor
90 for the master side of the pty, and calls
92 for the slave pty. In the parent process, it closes the descriptor for the
93 slave side of the pty. The arguments
99 have the same meaning as described for
103 returns 0 on success, or -1 on failure.
106 returns -1 on failure, 0 in the slave process, and the process ID of the
107 slave process in the parent process.
111 will set the global variable
118 may set it to any value as described for
132 The calling process must have an effective UID of super-user in order
133 to perform all the intended actions. No notification will occur if
137 failed to proceed with one of the described steps, as long as they could
138 at least allocate the pty at all (and create the new process in the case