Guida avanzata di scripting Bash - Portale Posta DMI

is_number() {
[ "$#" -eq 1 ] || return 1 # is blank?
[ x"$1" == ’x0’ ] && return 0 # is zero?
local -i tst
let tst=$1 2>/dev/null # else is numeric!
return $?
}
# This function described in is_address.bash.
# is_address
is_address() {
[ $# -eq 1 ] || return 1 # Blank ==> false
local -a _ia_input
local IFS=${ADR_IFS}
_ia_input=( $1 )
if [ ${#_ia_input[@]} -eq 4 ] &&
is_number ${_ia_input[0]} &&
is_number ${_ia_input[1]} &&
is_number ${_ia_input[2]} &&
is_number ${_ia_input[3]} &&
[ ${_ia_input[0]} -lt 256 ] &&
[ ${_ia_input[1]} -lt 256 ] &&
[ ${_ia_input[2]} -lt 256 ] &&
[ ${_ia_input[3]} -lt 256 ]
then
return 0
else
return 1
fi
}
# This function described in split_ip.bash.
# split_ip []
split_ip() {
[ $# -eq 3 ] || # Either three
[ $# -eq 2 ] || return 1 #+ or two arguments
local -a _si_input
local IFS=${ADR_IFS}
_si_input=( $1 )
IFS=${WSP_IFS}
eval $2=\(\ \$\{_si_input\[@\]\}\ \)
if [ $# -eq 3 ]
then
# Build query order array.
local -a _dns_ip
_dns_ip[0]=${_si_input[3]}
_dns_ip[1]=${_si_input[2]}
_dns_ip[2]=${_si_input[1]}
_dns_ip[3]=${_si_input[0]}
eval $3=\(\ \$\{_dns_ip\[@\]\}\ \)
fi
return 0
}
Appendice A. Script aggiuntivi
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