Function registerSession

src/utils/concurrentSessions.ts:59–109

()

 * Errors logged to debug, never thrown.
 */
export async function registerSession(): Promise<boolean> {
  if (getAgentId() != null) return false

  const kind: SessionKind = envSessionKind() ?? 'interactive'
  const dir = getSessionsDir()
  const pidFile = join(dir, `${process.pid}.json`)

  registerCleanup(async () => {
    try {
      await unlink(pidFile)
    } catch {
      // ENOENT is fine (already deleted or never written)
    }
  })

  try {
    await mkdir(dir, { recursive: true, mode: 0o700 })
    await chmod(dir, 0o700)
    await writeFile(
      pidFile,
      jsonStringify({
        pid: process.pid,
        sessionId: getSessionId(),
        cwd: getOriginalCwd(),
        startedAt: Date.now(),
        kind,
        entrypoint: process.env.CLAUDE_CODE_ENTRYPOINT,
        ...(feature('UDS_INBOX')
          ? { messagingSocketPath: process.env.CLAUDE_CODE_MESSAGING_SOCKET }
          : {}),
        ...(feature('BG_SESSIONS')
          ? {
              name: process.env.CLAUDE_CODE_SESSION_NAME,
              logPath: process.env.CLAUDE_CODE_SESSION_LOG,
              agent: process.env.CLAUDE_CODE_AGENT,
            }
          : {}),
      }),
    )
    // --resume / /resume mutates getSessionId() via switchSession. Without
    // this, the PID file's sessionId goes stale and `claude ps` sparkline
    // reads the wrong transcript.
    onSessionSwitch(id => {
      void updatePidFile({ sessionId: id })
    })
    return true
  } catch (e) {
    logForDebugging(`[concurrentSessions] register failed: ${errorMessage(e)}`)
    return false
  }
}

/**
 * Update this session's name in its PID registry file so ListPeers