I am taking input as memory ex. 10M or 50G or 50 K
and I want to check this much size available in file system. for that I'm using df -h command
df -Ph . | awk 'NR==2 {print $4}' I am getting 140M and my input may vary like 10k , 10M and 10G
EX:
my input is 20G and available memory in filesystem is 140M
So now how can I compare these two sizes (50G >140M ?) and echo output result.
You can also use -h with sort
Example
$cat <<EOF | sort -h 50G 140M 10M 50K EOF Result :
50K 10M 140M 50G Explanation:
-h, --human-numeric-sort, compare human readable numbers (e.g., 2K 1G)
Or inside a bash :
compare() { cat <<EOF | sort -h $1 $2 EOF } set $(compare 50G 140M) echo "$1 <= $2" Result:
140M <= 50G Another way to write compare :
compare() { echo -e "$1 \0 $2" | sort -zh } convert your available and input values to Kb and compare it..
#!/bin/bash echo -n "Enter the value ( value should end with G/M/K): " read DISK_VALUE AVAILABLE_SPACE=$(df -h . | awk 'NR==2{print $4}') AVAILABLE_SPACE_IN_KB=$(echo "${AVAILABLE_SPACE}" | awk '/M$/{print ($0+0)*1024}/G$/{print ($0+0)*1024*1024}/K$/{print $0+0}') COMPARE_VALUE_IN_KB=$(echo "${DISK_VALUE}" | awk '/M$/{print ($0+0)*1024}/G$/{print ($0+0)*1024*1024}/K$/{print $0+0}') echo "AVAILABLE_SPACE_IN_KB : ${AVAILABLE_SPACE_IN_KB}" echo "COMPARE_VALUE_IN_KB : ${COMPARE_VALUE_IN_KB}" if [ "${AVAILABLE_SPACE_IN_KB}" -lt "${COMPARE_VALUE_IN_KB}" ] then echo "Available space (${AVAILABLE_SPACE}) is lesser than Given Value (${DISK_VALUE})" else echo "Available space (${AVAILABLE_SPACE}) is greater than Given Value (${DISK_VALUE})" fi $ bash a.sh Enter the value : 1000K AVAILABLE_SPACE_IN_KB : 100 COMPARE_VALUE_IN_KB : 1000 Available space (100K) is lesser than Given Value (1000K) $ bash a.sh Enter the value : 101M AVAILABLE_SPACE_IN_KB : 102400 COMPARE_VALUE_IN_KB : 103424 Available space (100M) is lesser than Given Value (101M) 