mmap(2) requires MAP_PRIVATE ^ MAP_SHARED for flags;

found by kristaps@ on Mac OS X

2 files changed, 6 insertions, 1 deletions

diff --git a/TODO b/TODO
index c0682053..9061d150 100644
--- a/TODO
+++ b/TODO
@@ -399,6 +399,10 @@
 * performance issues
 ************************************************************************
 
+- Why are we using MAP_SHARED, not MAP_PRIVATE for mmap(2)?
+  How does SQLITE_CONFIG_PAGECACHE actually work?  Document it!
+  from kristaps@  Sat, 09 Aug 2014 13:51:36 +0200
+
 Several areas can be cleaned up to make mandoc even faster.  These are 
 
 - improve hashing mechanism for macros (quite important: performance)
diff --git a/mansearch.c b/mansearch.c
index f9a8b39b..1fe1f594 100644
--- a/mansearch.c
+++ b/mansearch.c
@@ -123,7 +123,8 @@ mansearch_setup(int start)
 		}
 
 		pagecache = mmap(NULL, PC_PAGESIZE * PC_NUMPAGES,
-		    PROT_READ | PROT_WRITE, MAP_ANON, -1, 0);
+		    PROT_READ | PROT_WRITE,
+		    MAP_SHARED | MAP_ANON, -1, 0);
 
 		if (MAP_FAILED == pagecache) {
 			perror("mmap");