pub fn pid_cmdline(pid: u32) -> Option<String>Expand description
Return the command line of a specific pid, or None if the pid
is missing / unreadable / exited between query and answer.
v0.14.2 (#162 diagnostic, post-supervisor #170): when wire status
surfaces orphan pids, the operator wants to know “which session
is that daemon serving?” without grepping ps themselves —
closes the launchd-vs-session-isolation diagnostic gap honey-pine
burned multiple sessions on.
- Linux: read
/proc/<pid>/cmdline(NUL-separated, replace with spaces). - macOS / BSD:
ps -p <pid> -o command=(no header, single column). - Windows: PowerShell CIM
Get-CimInstance Win32_Process | Where {$_.ProcessId -eq <pid>} | Select CommandLine.
Conservative on failure: returns None rather than synthesizing a
placeholder. Callers should treat None as “annotation unavailable”,
not “process is dead” — process_alive is the liveness oracle.