Convert decimal to hexadecimal in UNIX shell scrip

问题:

In a UNIX shell script, what can I use to convert decimal numbers into hexadecimal? I thought od would do the trick, but it's not realizing I'm feeding it ASCII representations of numbers.

printf? Gross! Using it for now, but what else is available?

回答1:

echo "obase=16; 34" | bc

If you want to filter a whole file of integers, one per line:

( echo "obase=16" ; cat file_of_integers ) | bc

回答2:

Tried printf(1)?

printf "%x\n" 34
22

There are probably ways of doing that with builtin functions in all shells but it would be less portable. I've not checked the POSIX sh specs to see whether it has such capabilities.

回答3:

Hexidecimal to decimal:

$ echo $((0xfee10000))
4276158464

Decimal to hexadecimal:

$ printf '%x\n' 26
1a

回答4:

bash-4.2$ printf '%x\n' 4294967295
ffffffff

bash-4.2$ printf -v hex '%x' 4294967295
bash-4.2$ echo $hex
ffffffff

回答5:

Sorry my fault, try this...

#!/bin/bash
:

declare -r HEX_DIGITS="0123456789ABCDEF"

dec_value=$1
hex_value=""

until [ $dec_value == 0 ]; do

    rem_value=$((dec_value % 16))
    dec_value=$((dec_value / 16))

    hex_digit=${HEX_DIGITS:$rem_value:1}

    hex_value="${hex_digit}${hex_value}"

done

echo -e "${hex_value}"

Example:

$ ./dtoh 1024
400

回答6:

Try:

printf "%X\n" ${MY_NUMBER}

回答7:

In zsh you can do this sort of thing:

% typeset -i 16 y
% print $(( [#8] x = 32, y = 32 ))
8#40
% print $x $y
8#40 16#20
% setopt c_bases
% print $y
0x20

Example taken from zsh docs page about Arithmetic Evaluation.

I believe Bash has similar capabilities.

回答8:

xd() {
    printf "hex> "
    while read i
    do
        printf "dec  $(( 0x${i} ))\n\nhex> "
    done
}
dx() {
    printf "dec> "
    while read i
    do
        printf 'hex  %x\n\ndec> ' $i
    done
}

回答9:

In my case, I stumbled upon one issue with using printf solution:

$ printf "%x" 008 bash: printf: 008: invalid octal number

The easiest way was to use solution with bc, suggested in post higher:

$ bc <<< "obase=16; 008" 8

回答10:

# number conversion.

while `test $ans='y'`
do
    echo "Menu"
    echo "1.Decimal to Hexadecimal"
    echo "2.Decimal to Octal"
    echo "3.Hexadecimal to Binary"
    echo "4.Octal to Binary"
    echo "5.Hexadecimal to  Octal"
    echo "6.Octal to Hexadecimal"
    echo "7.Exit"

    read choice
    case $choice in

        1) echo "Enter the decimal no."
           read n
           hex=`echo "ibase=10;obase=16;$n"|bc`
           echo "The hexadecimal no. is $hex"
           ;;

        2) echo "Enter the decimal no."
           read n
           oct=`echo "ibase=10;obase=8;$n"|bc`
           echo "The octal no. is $oct"
           ;;

        3) echo "Enter the hexadecimal no."
           read n
           binary=`echo "ibase=16;obase=2;$n"|bc`
           echo "The binary no. is $binary"
           ;;

        4) echo "Enter the octal no."
           read n
           binary=`echo "ibase=8;obase=2;$n"|bc`
           echo "The binary no. is $binary"
           ;;

        5) echo "Enter the hexadecimal no."
           read n
           oct=`echo "ibase=16;obase=8;$n"|bc`
           echo "The octal no. is $oct"
           ;;

        6) echo "Enter the octal no."
           read n
           hex=`echo "ibase=8;obase=16;$n"|bc`
           echo "The hexadecimal no. is $hex"
           ;;

        7) exit 
        ;;
        *) echo "invalid no." 
        ;;

    esac
done

回答11:

This is not a shell script, but it is the cli tool I'm using to convert numbers among bin/oct/dec/hex:

    #!/usr/bin/perl

    if (@ARGV < 2) {
      printf("Convert numbers among bin/oct/dec/hex\n");
      printf("\nUsage: base b/o/d/x num num2 ... \n");
      exit;
    }

    for ($i=1; $i<@ARGV; $i++) {
      if ($ARGV[0] eq "b") {
                    $num = oct("0b$ARGV[$i]");
      } elsif ($ARGV[0] eq "o") {
                    $num = oct($ARGV[$i]);
      } elsif ($ARGV[0] eq "d") {
                    $num = $ARGV[$i];
      } elsif ($ARGV[0] eq "h") {
                    $num = hex($ARGV[$i]);
      } else {
                    printf("Usage: base b/o/d/x num num2 ... \n");
                    exit;
      }
      printf("0x%x = 0d%d = 0%o = 0b%b\n", $num, $num, $num, $num);
    }