updated for version 7.4.235
Problem: It is not easy to get the full path of a command.
Solution: Add the exepath() function.
diff --git a/src/proto/os_unix.pro b/src/proto/os_unix.pro
index e4cad51..a59b6aa 100644
--- a/src/proto/os_unix.pro
+++ b/src/proto/os_unix.pro
@@ -42,7 +42,7 @@
void mch_free_acl __ARGS((vim_acl_T aclent));
void mch_hide __ARGS((char_u *name));
int mch_isdir __ARGS((char_u *name));
-int mch_can_exe __ARGS((char_u *name));
+int mch_can_exe __ARGS((char_u *name, char_u **path));
int mch_nodetype __ARGS((char_u *name));
void mch_early_init __ARGS((void));
void mch_free_mem __ARGS((void));