Human readable to KB

[damade]

Hi everyone !!

How can i convert an output in Human Readable size to KB ?
I have seen many examples in the opposite but none in order to transform (Mb, Gb, etc ) to KB

Thanks

[atreyu]

Are you using a specific program that outputs size, and you want to pass some flag to do this?

Or are you saying, you have a number (in MB, GB, etc.) and you manually want to convert it?

If the former, it depends - what is the prog? If the later (which is what i think you mean), do something like this:

#!/bin/bash
[ $# -ne 2 ] && echo "Usage: <NUMBER> <MB|GB>" && exit 1
num=$1
unit=$2
if [ $unit == 'MB' ]; then
  kb=$(printf '%.0f' $(echo $num \* 1024|bc -l))
  echo $num $unit = $kb KB
elif [ "$unit" == 'GB' ]; then
  kb=$(printf '%.0f' $(echo $num \* 1048576|bc -l))
  echo $num $unit = $kb KB
else
  echo "unit \`$unit' unsupported"
  exit 1
fi

[damade]

i can filter some commands to get this output

34m
1078
345m
4845
50m
1,2g
201m
2045

default is kb. if the value is scalated, the letter m or g is added.
I want all in KB

[atreyu]

okay, so try this: a single number is passed to this script (any one from the filtered list you provided), and it is checked to figure out what unit it is in. then it is passed to the original code (slightly modified) which is now a function.

#!/bin/bash
[ $# -ne 1 ] && echo "Usage: $0 <input>" && exit 1
input=$1

# mb
echo $input|grep -qi m$
if [ $? -eq 0 ]; then
  num=$(echo $input|sed -e 's|m$||i')
  unit='MB'
else
  # gb
  echo $input|grep -qi g$
  if [ $? -eq 0 ]; then
    num=$(echo $input|sed -e 's|g$||i')
    unit='GB'
  else
    echo $input|grep -q ^[0-9]*$
    if [ $? -ne 0 ]; then
      echo "Unexpected input \`$input'"
      exit 1
    fi
    # kb
    num=$input
    unit='KB'
  fi
fi

function convert_to_kb() {
  [ $# -ne 2 ] && echo "Usage: <NUMBER> <MB|GB>" && return 1
  num=$1
  unit=$2
  if [ $unit == 'MB' ]; then
    kb=$(printf '%.0f' $(echo $num \* 1024|bc -l))
    echo $num $unit = $kb KB
  elif [ "$unit" == 'GB' ]; then
    kb=$(printf '%.0f' $(echo $num \* 1048576|bc -l))
    echo $num $unit = $kb KB
  else
    echo "unit \`$unit' unsupported" >&2
    return 1
  fi
}

convert_to_kb $num $unit