sccmap

Extract strongly connected components of one or more directed graphs

$ sccmap -S [path/to/input1.gv path/to/input2.gv ...] > [path/to/output.gv]

$ sccmap -v -s [path/to/input1.gv path/to/input2.gv ...]

$ sccmap -?

sccmap [options]
sccmap [-a|-d|-l] [-f config_file] [-n slot_number] [-r reader_name] [-v] [-?]

-a
    Add a new reader mapping. This option typically requires specifying both a -n (slot number) and a -r (reader name).

-d
    Delete an existing reader mapping. This option requires specifying either a -n (slot number) or a -r (reader name) to identify the mapping to be deleted.

-l
    List all currently configured reader mappings. This provides an overview of how physical readers are assigned to logical slots.

-f config_file
    Specify an alternative configuration file path. By default, sccmap uses a standard OpenCT configuration file, often located in /etc/openct/ or /etc/.

-n slot_number
    The logical slot number (typically 0-indexed) to which a reader is mapped or from which a mapping is deleted. Used with -a or -d.

-r reader_name
    The physical name of the smart card reader as detected by the system. Used with -a or -d to specify which reader to map or unmap.

-v
    Enable verbose output, providing more detailed information about the operation being performed.

-?
    Display a brief help message and exit, showing common usage options.

sccmap is a utility from the OpenCT (OpenCard Framework Toolkit) project used to manage and configure how smart card readers are presented and mapped within the scc (Smart Card Connector) daemon.

It allows administrators to define logical slots for physical readers, enabling specific reader configurations, assigning particular readers to fixed slot numbers, or even disabling certain readers. This is particularly useful in environments with multiple smart card readers, where applications might expect readers at specific slot indices, or where fine-grained control over reader visibility and behavior is required. Changes made with sccmap typically affect the scc daemon's operational behavior and persist through configuration files.

Using sccmap typically requires root privileges to modify system-wide configuration files.

Changes made to reader mappings usually require restarting the scc daemon for them to take effect. sccmap configures the OpenCT-specific scc daemon, not the more common PCSC-Lite pcscd daemon, though both handle smart card access.

sccmap primarily interacts with the scc.conf configuration file, typically located in /etc/openct/ or /etc/. This file stores the persistent mapping definitions that the scc daemon reads upon startup. Users should be cautious when manually editing this file, as sccmap provides a safer, programmatic interface for modifications.

For changes to take effect, the scc daemon must typically be restarted after running sccmap. This ensures that the daemon re-reads its configuration and applies the new reader mappings.

sccmap is a component of the OpenCT (OpenCard Framework Toolkit) project, which provides a framework for smart card readers and smart cards under Linux. OpenCT was developed to offer a unified interface for various smart card readers, especially before PCSC-Lite became the predominant standard for smart card access on Linux.

sccmap specifically addresses the configuration needs for the scc daemon within this framework, allowing for flexible management of reader resources. Its usage has become less common as pcscd has gained wider adoption, but it remains relevant in systems specifically utilizing the OpenCT stack.

scc(8), scc_selftest(1), pcscd(8), openct(7)