Ascii/Hex convert in bash
BashAsciiHexBash Problem Overview
I'm now doing it this way:
[root@~]# echo Aa|hexdump -v
0000000 6141 000a
0000003
[root@~]# echo -e "\x41\x41\x41\x41"
AAAA
But it's not exactly behaving as I wanted,
the hex form of Aa
should be 4161
,but the output is 6141 000a
,which seems not making sense.
and when performing hex to ascii,is there another utility so that I don't need the prefix \x
?
Bash Solutions
Solution 1 - Bash
The reason is because hexdump
by default prints out 16-bit integers, not bytes. If your system has them, hd
(or hexdump -C
) or xxd
will provide less surprising outputs - if not, od -t x1
is a POSIX-standard way to get byte-by-byte hex output. You can use od -t x1c
to show both the byte hex values and the corresponding letters.
If you have xxd
(which ships with vim), you can use xxd -r
to convert back from hex (from the same format xxd
produces). If you just have plain hex (just the '4161', which is produced by xxd -p
) you can use xxd -r -p
to convert back.
Solution 2 - Bash
For the first part, try
echo Aa | od -t x1
It prints byte-by-byte
$ echo Aa | od -t x1
0000000 41 61 0a
0000003
The 0a
is the implicit newline that echo produces.
Use echo -n
or printf
instead.
$ printf Aa | od -t x1
0000000 41 61
0000002
Solution 3 - Bash
$> printf "%x%x\n" "'A" "'a"
4161
Solution 4 - Bash
For single line solution:
echo "Hello World" | xxd -ps -c 200 | tr -d '\n'
It will print:
48656c6c6f20576f726c640a
or for files:
cat /path/to/file | xxd -ps -c 200 | tr -d '\n'
For reverse operation:
echo '48656c6c6f20576f726c640a' | xxd -ps -r
It will print:
Hello World
Solution 5 - Bash
With bash :
a=abcdefghij
for ((i=0;i<${#a};i++));do printf %02X \'${a:$i:1};done
6162636465666768696A
Solution 6 - Bash
I don't know how it crazy it looks but it does the job really well
ascii2hex(){ a="$@";s=0000000;printf "$a" | hexdump | grep "^$s"| sed s/' '//g| sed s/^$s//;}
Created this when I was trying to see my name in HEX ;) use how can you use it :)
Solution 7 - Bash
Text2Conv="Aa"
for letter in $(echo "$Text2Conv" | sed "s/\(.\)/'\1 /g");do printf '%x' "$letter";done
4161
The trick is using sed to parse the Text2Conv to format we can then seperate anf loop using for.
Solution 8 - Bash
I use:
> echo Aa | tr -d '\n' | xxd -p
4161
> echo 414161 | tr -d '\n' | xxd -r -p
AAa
The tr -d '\n'
will trim any possible newlines in your input
Solution 9 - Bash
here a little script I wrote to convert ascii to hex. hope it helps:
echo '0x'"`echo 'ASCII INPUT GOES HERE' | hexdump -vC | awk 'BEGIN {IFS="\t"} {$1=""; print }' | awk '{sub(/\|.*/,"")}1' | tr -d '\n' | tr -d ' '`" | rev | cut -c 3- | rev
Solution 10 - Bash
SteinAir's answer above was helpful to me -- thank you! And below is a way it inspired, to convert hex strings to ascii:
for h in $(echo "4161" | sed "s/\(..\)/\1 /g"); do printf `echo "\x$h"`;done
Aa
Solution 11 - Bash
echo -n Aa | hexdump -e '/1 "%02x"'; echo
Solution 12 - Bash
Finally got the correct thing
echo "Hello, world!" | tr -d '\n' | xxd -ps -c 200
Solution 13 - Bash
according to http://mylinuxbook.com/hexdump/ you might use the hexdump format parameter
echo Aa | hexdump -C -e '/1 "%02X"'
will return 4161
to add an extra linefeed at the end, append another formatter.
BUT: the format given above will give multiplier outputs for repetitive characters
$ printf "Hello" | hexdump -e '/1 "%02X"'
48656C*
6F
instead of
48656c6c6f
Solution 14 - Bash
jcomeau@aspire:~$ echo -n The quick brown fox jumps over the lazy dog | python -c "print raw_input().encode('hex'),"
54686520717569636b2062726f776e20666f78206a756d7073206f76657220746865206c617a7920646f67
jcomeau@aspire:~$ echo -n The quick brown fox jumps over the lazy dog | python -c "print raw_input().encode('hex')," | python -c "print raw_input().decode('hex'),"
The quick brown fox jumps over the lazy dog
it could be done with Python3 as well, but differently, and I'm a lazy dog.
Solution 15 - Bash
echo append a carriage return at the end.
Use
echo -e
to remove the extra 0x0A
Also, hexdump does not work byte-per-byte as default. This is why it shows you bytes in a weird endianess and why it shows you an extra 0x00.