fifo.4 --> fifo.7

man2/open.2

@@ -245,7 +245,7 @@ When possible, the file is opened in non-blocking mode. Neither the
 nor any subsequent operations on the file descriptor which is
 returned will cause the calling process to wait.
 For the handling of FIFOs (named pipes), see also
-.BR fifo (4).
+.BR fifo (7).
 For a discussion of the effect of
 .BR O_NONBLOCK
 in conjunction with mandatory file locks and with file leases, see
@@ -556,4 +556,4 @@ corresponding to the flags \fBO_SYNC\fR, \fBO_DSYNC\fR and
 .BR unlink (2),
 .BR write (2),
 .BR fopen (3),
-.BR fifo (4)
+.BR fifo (7)

man3/mkfifo.3

@@ -51,7 +51,7 @@ However, it has to be open at both ends simultaneously before you can
 proceed to do any input or output operations on it.  Opening a FIFO
 for reading normally blocks until some other process opens the same
 FIFO for writing, and vice versa. See
-.BR fifo (4)
+.BR fifo (7)
 for non-blocking handling of FIFO special files.
 .SH "RETURN VALUE"
 On success \fImkfifo\fP() returns 0.  In
@@ -97,4 +97,4 @@ POSIX.1
 .BR umask (2),
 .BR write (2),
 .BR mkfifoat (3),
-.BR fifo (4)
+.BR fifo (7)

man7/pipe.7

@@ -54,7 +54,7 @@ flag; the write end is opened using the
 .B O_WRONLY
 flag.
 See
-.BR fifo (4)
+.BR fifo (7)
 for further details.
 .IR Note : 
 although FIFOs have a pathname in the file system,
@@ -235,5 +235,5 @@ bidirectional pipe semantics.
 .BR socketpair (2),
 .BR stat (2),
 .BR mkfifo (3),
-.BR fifo (4),
-.BR epoll (7)
+.BR epoll (7),
+.BR fifo (7)