The PTY approach caused isatty() to return true for services using
the log directive, triggering programs like fprintd (using glib) to
emit ANSI escape codes and other TTY-specific formatting in syslog.
Using a standard pipe ensures isatty() correctly returns false, so
programs produce plain text output suitable for logging.
For services that require line-buffered output, users can wrap the
command with `stdbuf -oL` as documented in doc/config/logging.md.
Fixes#455
Signed-off-by: Joachim Wiberg <troglobit@gmail.com>
Implement Linux capability support for services, allowing them to run
with minimal required privileges instead of running as root. This uses
the modern IAB (Inheritable, Ambient, Bounding) API from libcap.
Joachim Wiberg