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aachyee/cidr-to-netmask.sh

Forked from kwilczynski/cidr-to-netmask.sh
Created September 24, 2020 16:30
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CIDR to netmask in bash.
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cidr-to-netmask.sh
# Return netmask for a given network and CIDR.
cidr_to_netmask() {
value=$(( 0xffffffff ^ ((1 << (32 - $2)) - 1) ))
echo "$(( (value >> 24) & 0xff )).$(( (value >> 16) & 0xff )).$(( (value >> 8) & 0xff )).$(( value & 0xff ))"
}
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