Context: filereadertest Exten:s
 Using a string, feature is set to ---ABC123--- and is 6 long
 Using a variable, feature2 is set to ---ABC123--- and is 6 long
 Using a string with shift method, feature3 is set to ---ABC123--- and is 6 long
Before file: ---1--- len 1 after file: ---1--- LEN 2 hexdump:00000000  31                                                |1|
Before file: ---12--- len 2 after file: ---12--- LEN 2 hexdump:00000000  31 32                                             |12|
Before file: ---123--- len 3 after file: ---123--- LEN 3 hexdump:00000000  31 32 33                                          |123|
Before file: ---1234--- len 4 after file: ---1234--- LEN 4 hexdump:00000000  31 32 33 34                                       |1234|
Before file: ---12345--- len 5 after file: ---12345--- LEN 5 hexdump:00000000  31 32 33 34 35                                    |12345|
Before file: ---123456--- len 6 after file: ---123456--- LEN 6 hexdump:00000000  31 32 33 34 35 36                                 |123456|
Before file: ---A--- len 1 after file: ---A--- LEN 2 hexdump:00000000  41                                                |A|
Before file: ---AB--- len 2 after file: ---AB--- LEN 2 hexdump:00000000  41 42                                             |AB|
Before file: ---ABC--- len 3 after file: ---ABC--- LEN 3 hexdump:00000000  41 42 43                                          |ABC|
Before file: ---ABCD--- len 4 after file: ---ABCD--- LEN 4 hexdump:00000000  41 42 43 44                                       |ABCD|
Before file: ---ABCDE--- len 5 after file: ---ABCDE--- LEN 5 hexdump:00000000  41 42 43 44 45                                    |ABCDE|
Before file: ---ABC123--- len 6 after file: ---ABC123--- LEN 6 hexdump:00000000  41 42 43 31 32 33                                 |ABC123|