to connect to unix-domain sockets the `unix' pledge is needed and also unveil "w". gmid can't mutate files because it doesn't pledge `wpath' nor `cpath'.

breaks on some distro and needs further investigations; it's not that interesting fortunately.

undocumented flag to dump to stdout the request before doing it. Not useful, it's debugging leftover.

Both Linux and OpenBSD have LOGIN_NAME_MAX available when including limits.h, FreeBSD, Darwin and possibly others don't. FreeBSD (and maybe Darwin) have MAXLOGNAME, so try to use that if available. Otherwise use _POSIX_LOGIN_NAME_MAX, but only has a fallback since it has a lower value (9 at the time of writing). If everything fails, use 32 which is what OpenBSD use by default; OpenSMTPd also defaults to it. (compat copied from kamid.)

The code in fcgi_req to send the custom params set in the config file was placed inside the conditional for `tls_peer_cert_provided`, so the custom parameters would not be sent if a client certificate is not provided.