// test: hexdump.exe -i hexdump.c -e ' s//' 2>&1 | grep -q 'erroneous pattern'
// test: hexdump.exe -i hexdump.c -e ' s/\x41BCD/2041/' 2>&1 | grep -q "can't find pattern"
// test: hexdump.exe -i hexdump.c -e ' s/cflags/414e5/' 2>&1 | grep -q 'erroneous sequence'
// test: hexdump.exe -i hexdump.c -e ' s//' 2>&1 | grep -q 'erroneous pattern'
// test: hexdump.exe -i hexdump.c -e ' s/\x41BCD/2041/' 2>&1 | grep -q "can't find pattern"
// test: hexdump.exe -i hexdump.c -e ' s/cflags/414e5/' 2>&1 | grep -q 'erroneous sequence'