resmgrd(8)

NAME

resmgrd - resource manager daemon

SYNOPSIS

resmgrd [-f configfile] [-s socket] [-p pidfile] [-kd]

DESCRIPTION

resmgrd is a resource manager that allows applications to access and lock device files. It supports hot-plugging,
i.e. devices can be added to a resource class as they
become available, and can be removed when unplugged.

Devices are grouped in so-called resource classes. Each device in a resource class has an associated flag that
defines whether applications are permitted to open it for
reading and writing, or for reading only. The devices in
a resource class can be defined in the static configura
tion file, but they can also be added and removed dynami
cally by a hotplugging daemon.

For most purposes, having a single resource class will be
enough, but you can have several if you want.

Access control to device files happens at the resource
class level as well. Users can be granted the right to
access devices from a certain resource class. Again,
access control can be defined statically in the configura
tion file, or dynamically.

Applications communicate with resmgrd through an AF_LOCAL socket. When the client wants to access a device file, it
asks the resource manager to do so. If permitted by the
access control lists, the resource manager will open the
device file and pass the open file descriptor back to the
client via the AF_LOCAL socket.

Additionally, applications can use the resource manager to
lock and unlock a device file. This happens via tradi
tional UUCP-style lock files in /var/lock. The main pur
pose of this is to allow applications using serial devices
to continue using UUCP-style locks.

All other operations, such as adding devices to a resource
class, or granting a user access to a class, are
restricted to the administrator.

SEE ALSO

resmgr.conf(5), resmgr(1).

AUTHOR

Olaf Kirch <okir@lst.de>

resmgrd(8)