Merge pull request rust-lang#145 from dhuseby/fixing_O_ACCMODE

Fixes rust-lang#144 by defining O_ACCMODE for BSD's

Author: alexcrichton

src/unix/bsd/freebsdlike/mod.rs

@@ -160,6 +160,7 @@ pub const TMP_MAX: ::c_uint = 308915776;
 pub const O_RDONLY: ::c_int = 0;
 pub const O_WRONLY: ::c_int = 1;
 pub const O_RDWR: ::c_int = 2;
+pub const O_ACCMODE: ::c_int = 3;
 pub const O_APPEND: ::c_int = 8;
 pub const O_CREAT: ::c_int = 512;
 pub const O_EXCL: ::c_int = 2048;

src/unix/bsd/openbsdlike/mod.rs

@@ -68,6 +68,7 @@ pub const L_tmpnam : ::c_uint = 1024;
 pub const O_RDONLY : ::c_int = 0;
 pub const O_WRONLY : ::c_int = 1;
 pub const O_RDWR : ::c_int = 2;
+pub const O_ACCMODE : ::c_int = 3;
 pub const O_APPEND : ::c_int = 8;
 pub const O_CREAT : ::c_int = 512;
 pub const O_EXCL : ::c_int = 2048;