c: kill TCP ports and wait until they are free (cross-platform: bash/powershell/cmd)

c.ps1

<#
  c - kill whatever is using one or more TCP ports and wait until each is free.
  Usage:  c <port1> [port2] [portN...]
  Internal timeout: 10s per port.
#>
param([Parameter(ValueFromRemainingArguments = $true)] [string[]] $Ports)

if (-not $Ports -or $Ports.Count -eq 0) {
    Write-Host "Usage: c <port1> [port2] [portN...]"
    exit 1
}

$timeout = 10
$rc = 0

foreach ($port in $Ports) {
    if ($port -notmatch '^\d+$') { Write-Warning "Skipping '$port' (not a port)"; continue }
    Write-Host "Waiting for port $port to close..."
    $start = Get-Date
    while ($true) {
        $procIds = @()
        try {
            $procIds = Get-NetTCPConnection -LocalPort $port -ErrorAction Stop |
                       Select-Object -ExpandProperty OwningProcess -Unique
        } catch {
            # Fallback via netstat (environments without the NetTCPIP module)
            $procIds = @(netstat -ano | Select-String ":$port\s" |
                         ForEach-Object { ($_ -split '\s+')[-1] } | Sort-Object -Unique)
        }
        $procIds = $procIds | Where-Object { $_ -and $_ -ne 0 }

        if (-not $procIds) { Write-Host "OK: port $port is free!"; break }

        foreach ($p in $procIds) { Stop-Process -Id $p -Force -ErrorAction SilentlyContinue }

        if (((Get-Date) - $start).TotalSeconds -ge $timeout) {
            Write-Warning "Timeout: port $port still in use after ${timeout}s"
            $rc = 1
            break
        }
        Start-Sleep -Milliseconds 200
    }
}

exit $rc

c.sh

# c: kill whatever is using one or more TCP ports and wait until each is free.
# Usage: c <port1> [port2] [portN...]   (internal timeout: 10s per port)
c() {
    if [ $# -eq 0 ]; then
        echo "Usage: c <port1> [port2] [portN...]"
        return 1
    fi
    local timeout=10 rc=0
    for port in "$@"; do
        case "$port" in
            ''|*[!0-9]*) echo "Skipping '$port' (not a port)"; continue ;;
        esac
        echo "Waiting for port $port to close..."
        local start=$(date +%s)
        while true; do
            local pids=""
            if command -v lsof >/dev/null 2>&1; then
                pids=$(lsof -ti :"$port" 2>/dev/null)
            else
                pids=$(netstat -ano 2>/dev/null | awk -v p=":$port$" '$2 ~ p {print $NF}' | sort -u)
            fi
            if [ -z "$pids" ]; then
                echo "OK: port $port is free!"
                break
            fi
            for pid in $pids; do
                [ "$pid" = "0" ] && continue
                if command -v taskkill >/dev/null 2>&1; then
                    MSYS_NO_PATHCONV=1 taskkill /F /PID "$pid" >/dev/null 2>&1
                else
                    kill -9 "$pid" 2>/dev/null
                fi
            done
            if [ $(( $(date +%s) - start )) -ge $timeout ]; then
                echo "Timeout: port $port still in use after ${timeout}s"
                rc=1
                break
            fi
            sleep 0.2
        done
    done
    return $rc
}

install.ps1

# Installer for the `c` command on Windows PowerShell.
#   irm https://gist.githubusercontent.com/dansp89/63f387493d628ae95bb86ae1c0286523/raw/install.ps1 | iex
# Idempotent. Installs the engine into ~\.local\bin, a CMD wrapper and a profile function.

$ErrorActionPreference = 'Stop'
$bin = Join-Path $HOME '.local\bin'
New-Item -ItemType Directory -Path $bin -Force | Out-Null

# ── Engine c.ps1 ──────────────────────────────────────────────────────────────
$engine = @'
param([Parameter(ValueFromRemainingArguments = $true)] [string[]] $Ports)
if (-not $Ports -or $Ports.Count -eq 0) { Write-Host "Usage: c <port1> [port2] [portN...]"; exit 1 }
$timeout = 10; $rc = 0
foreach ($port in $Ports) {
    if ($port -notmatch '^\d+$') { Write-Warning "Skipping '$port' (not a port)"; continue }
    Write-Host "Waiting for port $port to close..."
    $start = Get-Date
    while ($true) {
        $procIds = @()
        try {
            $procIds = Get-NetTCPConnection -LocalPort $port -ErrorAction Stop |
                       Select-Object -ExpandProperty OwningProcess -Unique
        } catch {
            $procIds = @(netstat -ano | Select-String ":$port\s" |
                         ForEach-Object { ($_ -split '\s+')[-1] } | Sort-Object -Unique)
        }
        $procIds = $procIds | Where-Object { $_ -and $_ -ne 0 }
        if (-not $procIds) { Write-Host "OK: port $port is free!"; break }
        foreach ($p in $procIds) { Stop-Process -Id $p -Force -ErrorAction SilentlyContinue }
        if (((Get-Date) - $start).TotalSeconds -ge $timeout) {
            Write-Warning "Timeout: port $port still in use after ${timeout}s"; $rc = 1; break
        }
        Start-Sleep -Milliseconds 200
    }
}
exit $rc
'@
Set-Content -Path (Join-Path $bin 'c.ps1') -Value $engine -Encoding utf8
Write-Host "  -> $bin\c.ps1"

# ── CMD wrapper (plain ASCII, no <> in comments) ─────────────────────────────
$cmd = "@echo off`r`nrem c - kill TCP ports and wait until they are free.`r`npowershell -NoProfile -ExecutionPolicy RemoteSigned -File `"%~dp0c.ps1`" %*`r`n"
Set-Content -Path (Join-Path $bin 'c.cmd') -Value $cmd -Encoding ascii -NoNewline
Write-Host "  -> $bin\c.cmd"

# ── User PATH (so CMD can find c.cmd) ────────────────────────────────────────
$userPath = [Environment]::GetEnvironmentVariable('Path', 'User')
if (($userPath -split ';') -notcontains $bin) {
    [Environment]::SetEnvironmentVariable('Path', ($userPath.TrimEnd(';') + ';' + $bin), 'User')
    Write-Host "  -> added to user PATH: $bin"
}

# ── PowerShell profile function (idempotent) ─────────────────────────────────
$profileDir = Split-Path $PROFILE.CurrentUserAllHosts
if (-not (Test-Path $profileDir)) { New-Item -ItemType Directory -Path $profileDir -Force | Out-Null }
$profilePath = $PROFILE.CurrentUserAllHosts
$hasFunc = (Test-Path $profilePath) -and (Select-String -Path $profilePath -Pattern 'function c ' -Quiet)
if (-not $hasFunc) {
    Add-Content -Path $profilePath -Value "`n# c-killport`nfunction c { & `"`$HOME\.local\bin\c.ps1`" @args }" -Encoding utf8
    Write-Host "  -> function added to $profilePath"
}

Write-Host ""
Write-Host "Done! Open a new terminal (or run: . `$PROFILE)."
Write-Host "Usage: c 3000 8080 8473"

install.sh

#!/usr/bin/env bash
# Installer for the `c` command (kill TCP ports and wait until they are free).
#   curl -fsSL https://gist.githubusercontent.com/dansp89/63f387493d628ae95bb86ae1c0286523/raw/install.sh | bash
# Idempotent and cross-platform (Linux, macOS, Git Bash).
set -e

SHARE="$HOME/.local/share/c-killport"
BIN="$HOME/.local/bin"
mkdir -p "$SHARE" "$BIN"

MARKER="# >>> c-killport (source) >>>"

# ── Write the bash function (single-quoted heredoc = no escaping) ─────────────
cat > "$SHARE/c.sh" <<'CSH_EOF'
# c: kill whatever is using one or more TCP ports and wait until each is free.
# Usage: c <port1> [port2] [portN...]   (internal timeout: 10s per port)
c() {
    if [ $# -eq 0 ]; then
        echo "Usage: c <port1> [port2] [portN...]"
        return 1
    fi
    local timeout=10 rc=0
    for port in "$@"; do
        case "$port" in
            ''|*[!0-9]*) echo "Skipping '$port' (not a port)"; continue ;;
        esac
        echo "Waiting for port $port to close..."
        local start=$(date +%s)
        while true; do
            local pids=""
            if command -v lsof >/dev/null 2>&1; then
                pids=$(lsof -ti :"$port" 2>/dev/null)
            else
                pids=$(netstat -ano 2>/dev/null | awk -v p=":$port$" '$2 ~ p {print $NF}' | sort -u)
            fi
            if [ -z "$pids" ]; then
                echo "OK: port $port is free!"
                break
            fi
            for pid in $pids; do
                [ "$pid" = "0" ] && continue
                if command -v taskkill >/dev/null 2>&1; then
                    MSYS_NO_PATHCONV=1 taskkill /F /PID "$pid" >/dev/null 2>&1
                else
                    kill -9 "$pid" 2>/dev/null
                fi
            done
            if [ $(( $(date +%s) - start )) -ge $timeout ]; then
                echo "Timeout: port $port still in use after ${timeout}s"
                rc=1
                break
            fi
            sleep 0.2
        done
    done
    return $rc
}
CSH_EOF

# ── Add a 'source' line to the rc files (marker-guarded, idempotent) ──────────
add_source() {
    local rc="$1"
    [ -f "$rc" ] || touch "$rc"
    grep -qF "$MARKER" "$rc" && return 0
    {
        echo ""
        echo "$MARKER"
        echo "[ -f \"$SHARE/c.sh\" ] && . \"$SHARE/c.sh\""
        echo "# <<< c-killport (source) <<<"
    } >> "$rc"
    echo "  -> $rc"
}

echo "Installing the 'c' command..."
add_source "$HOME/.bashrc"
[ -f "$HOME/.zshrc" ] && add_source "$HOME/.zshrc"

# ── Bonus on Windows/Git Bash: also install for PowerShell and CMD ───────────
case "$(uname -s)" in
  MINGW*|MSYS*|CYGWIN*)
    echo "Windows detected — also installing for PowerShell and CMD..."
    # engine c.ps1
    curl -fsSL "https://gist.githubusercontent.com/dansp89/63f387493d628ae95bb86ae1c0286523/raw/c.ps1" -o "$BIN/c.ps1" 2>/dev/null || true
    # c.cmd wrapper
    printf '@echo off\r\nrem c - kill TCP ports and wait until they are free.\r\npowershell -NoProfile -ExecutionPolicy RemoteSigned -File "%%~dp0c.ps1" %%*\r\n' > "$BIN/c.cmd"
    echo "  -> $BIN/c.cmd  (make sure $BIN is on your PATH)"
    ;;
esac

echo ""
echo "Done! Open a new terminal or run: source ~/.bashrc"
echo "Usage: c 3000 8080 8473"