Minor clarifications for text on execlp() and execvp().

Removed FILES section, since it provides no useful additional info.

man3/exec.3

@@ -118,8 +118,7 @@ The other functions take the environment for the new process
 image from the external variable
 .I environ
 in the current process.
-.PP
-Some of these functions have special semantics.
+.SS Special semantics for execlp() and execvp()
 .PP
 The functions
 .BR execlp ()
@@ -150,8 +149,9 @@ If the header of a file isn't recognized (the attempted
 .BR execve ()
 returned
 .BR ENOEXEC ),
-these functions will execute the shell with the path of the file as its
-first argument.
+these functions will execute the shell 
+.RI ( /bin/sh )
+with the path of the file as its first argument.
 (If this attempt fails, no further searching is done.)
 .SH "RETURN VALUE"
 If any of the
@@ -166,9 +166,6 @@ All of these functions may fail and set
 .I errno
 for any of the errors specified for the library function
 .BR execve (2).
-.SH FILES
-.\" FIXME remove this section?
-.I /bin/sh
 .SH "CONFORMING TO"
 POSIX.1-2001.
 .SH NOTES