diff --git a/swix/swix.xcodeproj/xcuserdata/scott.xcuserdatad/xcdebugger/Breakpoints_v2.xcbkptlist b/swix/swix.xcodeproj/xcuserdata/scott.xcuserdatad/xcdebugger/Breakpoints_v2.xcbkptlist
index 3a27702..8eb1096 100644
--- a/swix/swix.xcodeproj/xcuserdata/scott.xcuserdatad/xcdebugger/Breakpoints_v2.xcbkptlist
+++ b/swix/swix.xcodeproj/xcuserdata/scott.xcuserdatad/xcdebugger/Breakpoints_v2.xcbkptlist
@@ -88,11 +88,11 @@
             ignoreCount = "0"
             continueAfterRunningActions = "No"
             filePath = "swix/swix/tests/tests.swift"
-            timestampString = "459447618.474421"
+            timestampString = "459449405.552788"
             startingColumnNumber = "9223372036854775807"
             endingColumnNumber = "9223372036854775807"
-            startingLineNumber = "277"
-            endingLineNumber = "277"
+            startingLineNumber = "279"
+            endingLineNumber = "279"
             landmarkName = "readWriteTests()"
             landmarkType = "5">
          </BreakpointContent>
diff --git a/swix/swix/main.swift b/swix/swix/main.swift
index 29ba924..1ed0317 100644
--- a/swix/swix/main.swift
+++ b/swix/swix/main.swift
@@ -10,5 +10,5 @@
 import Foundation
 import Swift
 
-swixTests()
+swixTests(run_io_tests: false)
 //swixSpeedTests()
\ No newline at end of file
diff --git a/swix/swix/swix/tests/tests.swift b/swix/swix/swix/tests/tests.swift
index 56d311c..e41e8da 100644
--- a/swix/swix/swix/tests/tests.swift
+++ b/swix/swix/swix/tests/tests.swift
@@ -10,7 +10,7 @@ import Foundation
 
 class swixTests {
     var N:Int
-    init(){
+    init(run_io_tests:Bool=true){
         print("running many simple tests")
         self.N = 10
         operatorTests()
@@ -21,8 +21,10 @@ class swixTests {
         print("   simple functions work as expected")
         twoDTests()
         print("   matrix convience elements work as expected")
-        readWriteTests()
-        print("   {read,write}_{binary,csv}, savefig work like Python... at least on OSX")
+        if run_io_tests {
+            readWriteTests()
+            print("   {read,write}_{binary,csv}, savefig work like Python... at least on OSX")
+        }
         complexTests()
         
         numberTests()