33 lines
458 B
Plaintext
33 lines
458 B
Plaintext
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#!/usr/bin/env bash
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set -eu
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script_name=$0
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die() {
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echo >&2 "$@"
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exit 1
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}
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about() {
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die "usage: $script_name <port_number>"
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}
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[ $# -lt 1 ] && about
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port_number=$1
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for _ in $(seq 40); do
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nc -z localhost "$port_number" >/dev/null 2>&1 && exit 0
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sleep .05
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done
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# send to &3 if open
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if { true >&3; } 2>/dev/null; then
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echo "Can't connect to port $port_number" >&3
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else
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echo "Can't connect to port $port_number" >&2
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fi
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exit 1
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