Replace all instances of err.strerror with err.

The strerror attribute contained only partial information about the
exception and produced some very confusing error messages.  By passing
err (the exception object itself) and letting it convert itself to a
string, the error messages are better.

Tools/scripts/trace.py

@@ -353,7 +353,7 @@ def create_results_log(results, dirname = ".", show_missing = 1,
             lines = open(filename, 'r').readlines()
         except IOError, err:
             print >> sys.stderr, "trace: Could not open %s for reading " \
-                  "because: %s - skipping" % (`filename`, err.strerror)
+                  "because: %s - skipping" % (`filename`, err)
             continue
 
         try:
@@ -361,7 +361,7 @@ def create_results_log(results, dirname = ".", show_missing = 1,
         except IOError, err:
             sys.stderr.write(
                 '%s: Could not open %s for writing because: %s" \
-                "- skipping\n' % ("trace", `listfilename`, err.strerror))
+                "- skipping\n' % ("trace", `listfilename`, err))
             continue
 
         # If desired, get a list of the line numbers which represent
@@ -416,7 +416,7 @@ def create_results_log(results, dirname = ".", show_missing = 1,
                              open(os.path.join(dirname, "modules"), "w"))
             except IOError, err:
                 sys.stderr.write("cannot save counts/modules " \
-                                 "files because %s" % err.strerror)
+                                 "files because %s" % err)
 
     if summary and sums:
         mods = sums.keys()
@@ -663,7 +663,7 @@ def main(argv = None):
             run(t.trace, 'execfile(' + `progname` + ')')
         except IOError, err:
             _err_exit("Cannot run file %s because: %s" % \
-                      (`sys.argv[0]`, err.strerror))
+                      (`sys.argv[0]`, err))
 
     elif count:
         t = Coverage(ignore)
@@ -671,7 +671,7 @@ def main(argv = None):
             run(t.trace, 'execfile(' + `progname` + ')')
         except IOError, err:
             _err_exit("Cannot run file %s because: %s" % \
-                      (`sys.argv[0]`, err.strerror))
+                      (`sys.argv[0]`, err))
         except SystemExit:
             pass
 
@@ -699,7 +699,7 @@ def main(argv = None):
                               open(counts_file, 'wb'))
             except IOError, err:
                 _err_exit("Cannot save counts file %s because: %s" % \
-                          (`counts_file`, err.strerror))
+                          (`counts_file`, err))
 
     elif report:
         old_counts, old_modules = marshal.load(open(counts_file, 'rb'))