BUG#12984 mysqltest.test: different output from "exec NonExistsinfComamdn"

mysql-test/r/mysqltest.result:
  Disable test for failing --exec and --system since output can't be piped to /dev/null on all platforms
mysql-test/t/mysqltest.test:
  Disable test for failing --exec and --system since output can't be piped to /dev/null on all platforms
  Avoid "echo -e" by using a temporary .sql file for tests that require more than one line.

mysql-test/r/mysqltest.result

@@ -179,7 +179,6 @@ source database
 echo message echo message
 
 mysqltest: At line 1: Empty variable
-mysqltest: At line 1: command "';' 2> /dev/null" failed
 mysqltest: At line 1: Missing argument in exec
 MySQL
 "MySQL"
@@ -301,7 +300,6 @@ mysqltest: At line 1: First argument to dec must be a variable (start with $)
 mysqltest: At line 1: End of line junk detected: "1000"
 mysqltest: At line 1: Missing arguments to system, nothing to do!
 mysqltest: At line 1: Missing arguments to system, nothing to do!
-mysqltest: At line 1: system command 'NonExistsinfComamdn 2> /dev/null' failed
 test
 test2
 test3

mysql-test/t/mysqltest.test

@@ -358,8 +358,11 @@ select 3 from t1 ;
 # Missing delimiter
 # The comment will be "sucked into" the sleep command since
 # delimiter is missing until after "show status"
+--system echo "sleep 4" > var/log/mysqltest.sql
+--system echo "# A comment" >> var/log/mysqltest.sql
+--system echo "show status;" >> var/log/mysqltest.sql
 --error 1
---exec echo -e "sleep 4\n # A comment\nshow status;" | $MYSQL_TEST 2>&1
+--exec $MYSQL_TEST < var/log/mysqltest.sql 2>&1
 
 #
 # Extra delimiter
@@ -423,8 +426,9 @@ echo ;
 # ----------------------------------------------------------------------------
 
 # Illegal use of exec
---error 1
---exec echo "--exec ';' 2> /dev/null" | $MYSQL_TEST 2>&1
+# Disabled, some shells prints the failed command regardless of pipes
+#--error 1
+#--exec echo "--exec ';' 2> /dev/null" | $MYSQL_TEST 2>&1
 
 --error 1
 --exec echo "--exec " | $MYSQL_TEST 2>&1
@@ -671,8 +675,9 @@ system echo "hej" > /dev/null;
 --exec echo "system;" | $MYSQL_TEST 2>&1
 --error 1
 --exec echo "system $NONEXISTSINFVAREABLI;" | $MYSQL_TEST 2>&1
---error 1
---exec echo "system NonExistsinfComamdn 2> /dev/null;" | $MYSQL_TEST 2>&1
+# Disabled, some shells prints the failed command regardless of pipes
+#--error 1
+#--exec echo "system NonExistsinfComamdn 2> /dev/null;" | $MYSQL_TEST 2>&1
 
 --disable_abort_on_error
 system NonExistsinfComamdn;
@@ -722,12 +727,21 @@ while ($i)
 --exec echo "end;" | $MYSQL_TEST 2>&1
 --error 1
 --exec echo "{;" | $MYSQL_TEST 2>&1
+
+--system echo "while (0)" > var/log/mysqltest.sql
+--system echo "echo hej;" >> var/log/mysqltest.sql
 --error 1
---exec echo -e "while (0)\necho hej;" | $MYSQL_TEST 2>&1
+--exec $MYSQL_TEST < var/log/mysqltest.sql 2>&1
+
+--system echo "while (0)" > var/log/mysqltest.sql
+--system echo "{echo hej;" >> var/log/mysqltest.sql
 --error 1
---exec echo -e "while (0)\n{echo hej;" | $MYSQL_TEST 2>&1
+--exec $MYSQL_TEST < var/log/mysqltest.sql 2>&1
+
+--system echo "while (0){" > var/log/mysqltest.sql
+--system echo "echo hej;" >> var/log/mysqltest.sql
 --error 1
---exec echo -e "while (0){\n echo hej;" | $MYSQL_TEST 2>&1
+--exec $MYSQL_TEST < var/log/mysqltest.sql 2>&1
 
 # ----------------------------------------------------------------------------
 # Test error messages returned from comments starting with a command