#define FIRST_PTY_LETTER 'p'
+#ifdef HAVE_DEV_PTMX
+
+/* This is the same definition as in usg5-4.h, but with sigblock/sigunblock
+ rather than sighold/sigrelse, which appear to be BSD4.1 specific and won't
+ work if POSIX_SIGNALS is defined. It may also be appropriate for SVR4.x
+ (x<2) but I'm not sure. fnf@cygnus.com */
+/* This sets the name of the slave side of the PTY. On SysVr4,
+ grantpt(3) forks a subprocess, so keep sigchld_handler() from
+ intercepting that death. If any child but grantpt's should die
+ within, it should be caught after sigrelse(2). */
+
+#undef FIRST_PTY_LETTER
+#define FIRST_PTY_LETTER 'z'
+
+/* This sets the name of the master side of the PTY. */
+#define PTY_NAME_SPRINTF strcpy (pty_name, "/dev/ptmx");
+
+#undef PTY_TTY_NAME_SPRINTF
+#define PTY_TTY_NAME_SPRINTF \
+ { \
+ char *ptsname (), *ptyname; \
+ \
+ sigblock (sigmask (SIGCLD)); \
+ if (grantpt (fd) == -1) \
+ { close (fd); return -1; } \
+ sigunblock (sigmask (SIGCLD)); \
+ if (unlockpt (fd) == -1) \
+ { close (fd); return -1; } \
+ if (!(ptyname = ptsname (fd))) \
+ { close (fd); return -1; } \
+ strncpy (pty_name, ptyname, sizeof (pty_name)); \
+ pty_name[sizeof (pty_name) - 1] = 0; \
+ }
+
+#endif /* HAVE_DEV_PTMX */
+
/*
* Define HAVE_TERMIOS if the system provides POSIX-style
* functions and macros for terminal control.