Don't assume that pressures are always positive

When planning a dive, the dive could use more gas than is in the cylinder.
So getting a negative end pressure is a useful indication to the user that
there plan might not be a good one.

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

1 files changed, 1 insertions, 1 deletions

diff --git a/dive.h b/dive.h
index 50bd2df39..03acea496 100644
--- a/dive.h
+++ b/dive.h
@@ -68,7 +68,7 @@ typedef struct
 	const char *description; /* "integrated", "belt", "ankle" */
 } weightsystem_t;
 
-extern int get_pressure_units(unsigned int mb, const char **units);
+extern int get_pressure_units(int mb, const char **units);
 extern double get_depth_units(int mm, int *frac, const char **units);
 extern double get_volume_units(unsigned int ml, int *frac, const char **units);
 extern double get_temp_units(unsigned int mk, const char **units);