Use char as datatype for the byte that are read with my_fgetc, fixes problem with

mysqltest.test on Solaris and Mac. write_file produced nice files with all zeroes.

client/mysqltest.c

@@ -1810,7 +1810,7 @@ void my_ungetc(int c)
 void read_until_delimiter(DYNAMIC_STRING *ds,
                           DYNAMIC_STRING *ds_delimiter)
 {
-  int c;
+  char c;
   DBUG_ENTER("read_until_delimiter");
   DBUG_PRINT("enter", ("delimiter: %s, length: %d",
                        ds_delimiter->str, ds_delimiter->length));

mysql-test/mysql-test-run.pl

@@ -1421,7 +1421,7 @@ sub executable_setup () {
   {
     # Skip looking for exe_mysql_client_test as its not built by default
     # in 4.1 for windows.
-    exe_mysql_client_test= "unavailable";
+    $exe_mysql_client_test= "unavailable";
   }
   else
   {