bind: address already in use

[milahu]

im getting this error after killing and restarting the socks5 server

$ ./cmd/socks5/socks5
[socks5] 2023/11/29 17:40:38 listen tcp :1080: bind: address already in use

maybe the server is missing some cleanup code, to close all connections

after killing and restarting the socks5 server

im killing the server with control-c (sigint)
so the server should have enough time for cleanup

run.sh

#!/usr/bin/env bash

set -e

netstat_out="$(netstat -nap 2>/dev/null | grep -w 1080 || true)"
if [ -n "$netstat_out" ]; then
  echo "error: address already in use"
  echo "$netstat_out"
  if true; then
    exit 1
  else
    echo "killing worker procs using port 1080"
    netstat -nap 2>/dev/null | grep -w 1080 | awk '{ print $7 }' | cut -d/ -f1 | xargs kill
  fi
fi

cd cmd/socks5/ &&
go build &&
cd ../.. &&
./cmd/socks5/socks5 &
socks5_pid=$!;
echo socks5_pid: $socks5_pid;
sleep 1;
curl --proxy socks5h://localhost:1080 https://httpbin.org/ip;
kill $socks5_pid

$ ./run.sh 
socks5_pid: 371297
{
  "origin": "xxxxxxxxxxxxx"
}

$ ./run.sh 
error: address already in use
tcp6       0      0 :::1080                 :::*                    LISTEN      371359/./cmd/socks5 
tcp6       0      0 ::1:60936               ::1:1080                TIME_WAIT   -                   

problem: the worker process 371359 keeps running
after then main process 371297 was killed

[wzshiming]

cd cmd/socks5/ &&
go build &&
cd ../.. &&
./cmd/socks5/socks5 &
socks5_pid=$!;

The socks5_pid is not the pid of socks5 but the pipeline ... && ... && ... &

cd cmd/socks5/ &&
go build &&
cd ../..

#########################

./cmd/socks5/socks5 &
socks5_pid=$!

Separate builds and runs to get their pid correctly

[milahu]

facepalm. thanks!

run.sh

#!/usr/bin/env bash

set -e

proxy_port=1080

netstat_out="$(netstat -nap 2>/dev/null | grep -w $proxy_port || true)"
if [ -n "$netstat_out" ]; then
  echo "error: address already in use"
  echo "found $(echo "$netstat_out" | wc -l) open connections with port $proxy_port:"
  echo "$netstat_out"
  #if true; then
  if false; then
    exit 1
  else
    echo "killing worker procs using port $proxy_port"
    netstat -nap 2>/dev/null | grep -w $proxy_port | awk '{ print $7 }' | cut -d/ -f1 | grep -vxFe - | xargs -r kill
  fi
fi

cd cmd/socks5/
go build
cd ../..

./cmd/socks5/socks5 &

socks5_pid=$!;
echo socks5_pid: $socks5_pid;
sleep 2;

#if true; then
if false; then
  # socks5
  curl --no-keepalive --proxy socks5://localhost:$proxy_port https://httpbin.org/ip;
else
  # socks5h
  curl --no-keepalive --proxy socks5h://localhost:$proxy_port https://httpbin.org/ip;
fi

kill $socks5_pid

now after running some cycles, there are some open connections
which disappear after a few seconds

$ netstat -nap 2>/dev/null | grep -w 1080
tcp6       0      0 ::1:59198               ::1:1080                TIME_WAIT   -                   
tcp6       0      0 ::1:40238               ::1:1080                TIME_WAIT   -                   
tcp6       0      0 ::1:54384               ::1:1080                TIME_WAIT   -                   

but they are not blocking the start of a new proxy server