[PATCH 4/4] doc: check-man: save the result of successful runs

[Eric Wong <e@80x24.org>]

We can keep a stamp around if the corresponding manpage hasn't
changed to avoid re-running man(1) and awk(1).
---
 .gitignore               |  1 +
 Documentation/include.mk | 13 +++++++------
 2 files changed, 8 insertions(+), 6 deletions(-)

diff --git a/.gitignore b/.gitignore
index 66f165e2..167d08bf 100644
--- a/.gitignore
+++ b/.gitignore
@@ -12,6 +12,7 @@
 *.8
 *.html
 *.gz
+.*.cols
 /NEWS.html
 /NEWS.atom
 /NEWS
diff --git a/Documentation/include.mk b/Documentation/include.mk
index ea0498c1..651fdf30 100644
--- a/Documentation/include.mk
+++ b/Documentation/include.mk
@@ -93,14 +93,15 @@ doc_install :: install-man
 
 check :: check-man
 check_man = @echo CHECK80 $<;COLUMNS=80 $(MAN) ./$^ | \
-	$(AWK) '{gsub(/\b./,"")}length>80{print;err=1}END{exit(err)}' >&2
+	$(AWK) '{gsub(/\b./,"")}length>80{print;err=1}END{exit(err)}' >&2 \
+	&& >$@
 
-%.1.cols : %.1; $(check_man)
-%.5.cols : %.5; $(check_man)
-%.7.cols : %.7; $(check_man)
-%.8.cols : %.8; $(check_man)
+.%.1.cols : %.1; $(check_man)
+.%.5.cols : %.5; $(check_man)
+.%.7.cols : %.7; $(check_man)
+.%.8.cols : %.8; $(check_man)
 
-check-man :: $(addsuffix .cols, $(manpages))
+check-man :: $(addprefix .,$(addsuffix .cols, $(manpages)))
 
 manuals :=
 manuals += $(m1)