--- Libc/Libc-825.26/stdlib/grantpt.3
+++ Libc/Libc-1669.0.4/stdlib/grantpt.3
@@ -38,6 +38,7 @@
 .Nm grantpt ,
 .Nm posix_openpt ,
 .Nm ptsname ,
+.Nm ptsname_r ,
 .Nm unlockpt
 .Nd pseudo-terminal access functions
 .Sh SYNOPSIS
@@ -50,6 +51,12 @@
 .Fo ptsname
 .Fa "int fildes"
 .Fc
+.Ft "int"
+.Fo ptsname_r
+.Fa "int fildes"
+.Fa "char *buffer"
+.Fa "size_t buflen"
+.Fc
 .Ft int
 .Fo unlockpt
 .Fa "int fildes"
@@ -64,51 +71,58 @@
 The
 .Fn grantpt ,
 .Fn ptsname ,
+.Fn ptsname_r ,
 .Fn unlockpt ,
 and
 .Fn posix_openpt
 functions allow access to pseudo-terminal devices.
-The first three functions accept a file descriptor
-that references the master half of a pseudo-terminal pair.
+The first four functions accept a file descriptor
+that references the primary half of a pseudo-terminal pair.
 This file descriptor is created with
 .Fn posix_openpt .
 .Pp
 The
 .Fn grantpt
 function is used to establish ownership and permissions
-of the slave device counterpart to the master device
+of the replica device counterpart to the primary device
 specified with
 .Fa fildes .
-The slave device's ownership is set to the real user ID
+The replica device's ownership is set to the real user ID
 of the calling process; its permissions are set to
 user readable-writable and group writable.
-The group owner of the slave device is also set to the group
+The group owner of the replica device is also set to the group
 .Dq Li tty
 if it exists on the system; otherwise, it
 is left untouched.
 .Pp
 The
 .Fn ptsname
-function returns the full pathname of the slave device
-counterpart to the master device specified with
+and
+.Fn ptsname_r
+functions return the full pathname of the replica device
+counterpart to the primary device specified with
 .Fa fildes .
 This value can be used
-to subsequently open the appropriate slave after
+to subsequently open the appropriate replica after
 .Fn posix_openpt
 and
 .Fn grantpt
-have been called.
+have been called. The
+.Fn ptsname
+function is not guaranteed to be reentrant or thread safe. The
+.Fn ptsname_r
+function takes a buffer and length as arguments to avoid this problem.
 .Pp
 The
 .Fn unlockpt
-function unlocks the slave pseudo-terminal device associated
-with the master device to which
+function unlocks the replica pseudo-terminal device associated
+with the primary device to which
 .Fa fildes
 refers.
 .Pp
 The
 .Fn posix_openpt
-function opens the first available master pseudo-terminal
+function opens the first available primary pseudo-terminal
 device and returns a descriptor to it.
 The
 .Fa oflag
@@ -127,16 +141,22 @@
 The
 .Fn ptsname
 function returns a pointer to the name
-of the slave device on success; otherwise a
+of the replica device on success; otherwise a
 .Dv NULL
 pointer is returned and the global variable
 .Va errno
 is set to indicate the error.
 .Pp
 The
+.Fn ptsname_r
+function returns 0 if successful.  On failure, it returns -1 and the global variable
+.Va errno
+is set to indicate the error.
+.Pp
+The
 .Fn posix_openpt
 function returns a file descriptor to the first
-available master pseudo-terminal device on success;
+available primary pseudo-terminal device on success;
 otherwise \-1 is returned and the global variable
 .Va errno
 is set to indicate the error.
@@ -144,6 +164,7 @@
 The
 .Fn grantpt ,
 .Fn ptsname ,
+.Fn ptsname_r ,
 and
 .Fn unlockpt
 functions may fail and set
@@ -152,7 +173,25 @@
 .Bl -tag -width Er
 .It Bq Er EINVAL
 .Fa fildes
-is not a master pseudo-terminal device.
+is not a primary pseudo-terminal device.
+.El
+.Pp
+In addition, the
+.Fn ptsname_r
+function may set
+.Va errno
+to:
+.Bl -tag -width Er
+.It Bq Er EINVAL
+The
+.Va buffer
+argument is NULL.
+.El
+.Bl -tag -width Er
+.It Bq Er ERANGE
+The
+.Va bufsize
+argument is smaller than the length of the string to be returned.
 .El
 .Pp
 In addition, the
@@ -162,7 +201,7 @@
 to:
 .Bl -tag -width Er
 .It Bq Er EACCES
-The slave pseudo-terminal device could not be accessed.
+The replica pseudo-terminal device could not be accessed.
 .El
 .Pp
 The
@@ -181,6 +220,7 @@
 The
 .Fn grantpt ,
 .Fn ptsname ,
+.Fn ptsname_r ,
 and
 .Fn unlockpt
 functions may also fail and set