diff --git a/src/tests/add-ons/kernel/file_systems/bfs/bfs_shell/Jamfile b/src/tests/add-ons/kernel/file_systems/bfs/bfs_shell/Jamfile
index 577a958ac2..ddb32a2f29 100644
--- a/src/tests/add-ons/kernel/file_systems/bfs/bfs_shell/Jamfile
+++ b/src/tests/add-ons/kernel/file_systems/bfs/bfs_shell/Jamfile
@@ -50,10 +50,15 @@ SetupIncludes ;
 		malloc_debug_flags = -fcheck-memory-usage ;
 	}
 
-	# We need to use a wrapper for fstat() on non-BeOS systems.
-	local buildPlatformFstatDefines ;
+	# We need to use a wrapper for some POSIX calls on non-BeOS systems.
+	local buildPlatformDefines ;
 	if $(OS) != BEOS {
-		buildPlatformFstatDefines = build_platform_fstat=fs_shell_fstat ;
+		buildPlatformDefines =
+			open=build_platform_open
+			close=build_platform_close
+			fstat=build_platform_fstat
+			read_pos=build_platform_read_pos
+		;
 	}
 
 	local defines = [ FDefines USER
@@ -62,7 +67,7 @@ SetupIncludes ;
 		UNSAFE_GET_VNODE
 		#BFS_BIG_ENDIAN_ONLY
 		$(malloc_debug_defines)
-		$(buildPlatformFstatDefines)
+		$(buildPlatformDefines)
 	] ;
 	SubDirCcFlags $(defines) $(malloc_debug_flags) ;
 	SubDirC++Flags $(defines) -fno-exceptions -fno-rtti $(malloc_debug_flags)
diff --git a/src/tests/add-ons/kernel/file_systems/bfs/r5/Volume.cpp b/src/tests/add-ons/kernel/file_systems/bfs/r5/Volume.cpp
index 8d64a717a4..799a0f8c83 100644
--- a/src/tests/add-ons/kernel/file_systems/bfs/r5/Volume.cpp
+++ b/src/tests/add-ons/kernel/file_systems/bfs/r5/Volume.cpp
@@ -21,13 +21,6 @@
 #include <string.h>
 #include <ctype.h>
 
-// fs_shell support for build platforms whose struct stat is not compatible with ours
-#ifdef build_platform_fstat
-extern "C" int build_platform_fstat(int fd, struct stat *st);
-#else
-#	define build_platform_fstat fstat
-#endif
-
 
 static const int32 kDesiredAllocationGroups = 56;
 	// This is the number of allocation groups that will be tried
@@ -129,7 +122,7 @@ DeviceOpener::GetSize(off_t *_size, uint32 *_blockSize)
 	if (ioctl(fDevice, B_GET_GEOMETRY, &geometry) < 0) {
 		// maybe it's just a file
 		struct stat stat;
-		if (build_platform_fstat(fDevice, &stat) < 0)
+		if (fstat(fDevice, &stat) < 0)
 			return B_ERROR;
 
 		if (_size)
@@ -295,7 +288,7 @@ Volume::Mount(const char *deviceName, uint32 flags)
 	// check if it's a regular file, and if so, disable the cache for the
 	// underlaying file system
 	struct stat stat;
-	if (build_platform_fstat(fDevice, &stat) < 0)
+	if (fstat(fDevice, &stat) < 0)
 		RETURN_ERROR(B_ERROR);
 
 #ifndef NO_FILE_UNCACHED_IO