Include <stdio.h> in getpgrp/setpgrp probes for printf prototype.

C compilers typically issue a warning, but c++ compilers may abort with
an error.

diff --git a/Configure b/Configure
index 8d67b39..a50034f 100755 (executable)
--- a/Configure
+++ b/Configure
@@ -11289,6 +11289,7 @@ case "$d_getpgrp" in
        echo " "
        echo "Checking to see which flavor of getpgrp is in use..."
        $cat >try.c <<EOP
+#include <stdio.h>
 #$i_unistd I_UNISTD
 #include <sys/types.h>
 #ifdef I_UNISTD
@@ -11355,6 +11356,7 @@ case "$d_setpgrp" in
        echo " "
        echo "Checking to see which flavor of setpgrp is in use..."
        $cat >try.c <<EOP
+#include <stdio.h>
 #$i_unistd I_UNISTD
 #include <sys/types.h>
 #ifdef I_UNISTD