Sweep through the tree fixing mmap() usage:

  - Use MAP_FAILED instead of the constant -1 to indicate
    failure (required by POSIX).
  - Removed flag arguments of '0' (required by POSIX).
  - Fixed code which expected an error return of 0.
  - Fixed code which thought any address with the high bit set
    was an error.
  - Check for failure where no checks were present.

Discussed with:	bde

2 files changed, 2 insertions, 2 deletions

diff --git a/usr.bin/tail/forward.c b/usr.bin/tail/forward.c
index 4b22eef..b9457af 100644
--- a/usr.bin/tail/forward.c
+++ b/usr.bin/tail/forward.c
@@ -210,7 +210,7 @@ rlines(fp, off, sbp)
 	}
 
 	if ((start = mmap(NULL, (size_t)size,
-	    PROT_READ, 0, fileno(fp), (off_t)0)) == (caddr_t)-1) {
+	    PROT_READ, MAP_SHARED, fileno(fp), (off_t)0)) == MAP_FAILED) {
 		ierr();
 		return;
 	}
diff --git a/usr.bin/tail/reverse.c b/usr.bin/tail/reverse.c
index 2653add..0a07f4f 100644
--- a/usr.bin/tail/reverse.c
+++ b/usr.bin/tail/reverse.c
@@ -125,7 +125,7 @@ r_reg(fp, style, off, sbp)
 	}
 
 	if ((start = mmap(NULL, (size_t)size,
-	    PROT_READ, 0, fileno(fp), (off_t)0)) == (caddr_t)-1) {
+	    PROT_READ, MAP_SHARED, fileno(fp), (off_t)0)) == MAP_FAILED) {
 		ierr();
 		return;
 	}