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Updated: July 2017

scdaemon (1)


scdaemon - Smartcard daemon for the GnuPG system


scdaemon [--homedir dir] [--options file] [options] --server
scdaemon  [--homedir  dir]  [--options  file]  [options] --daemon [com-


SCDAEMON(1)                    GNU Privacy Guard                   SCDAEMON(1)

       scdaemon - Smartcard daemon for the GnuPG system

       scdaemon [--homedir dir] [--options file] [options] --server
       scdaemon  [--homedir  dir]  [--options  file]  [options] --daemon [com-

       The scdaemon is a daemon to manage smartcards.  It is  usually  invoked
       by gpg-agent and in general not used directly.

       Commands  are  not  distinguished from options except for the fact that
       only one command is allowed.

              Print the program version and licensing information.   Not  that
              you can abbreviate this command.

       --help, -h
              Print  a  usage message summarizing the most useful command-line
              options.  Not that you can abbreviate this command.

              Print a list of all available options and  commands.   Not  that
              you can abbreviate this command.

              Run  in server mode and wait for commands on the stdin.  This is
              default mode is to create  a  socket  and  listen  for  commands

              Run in server mode and wait for commands on the stdin as well as
              on an additional Unix Domain socket.  The server command GETINFO
              may be used to get the name of that extra socket.

              Run  the  program in the background.  This option is required to
              prevent it from being accidentally running in the background.

       --options file
              Reads configuration from file instead of from the  default  per-
              user  configuration  file.   The  default  configuration file is
              named `scdaemon.conf' and expected  in  the  `.gnupg'  directory
              directly below the home directory of the user.

       --homedir dir
              Set the name of the home directory to dir. If this option is not
              used, the home directory defaults to  `~/.gnupg'.   It  is  only
              recognized  when  given  on the command line.  It also overrides
              any home  directory  stated  through  the  environment  variable
              `GNUPGHOME'  or  (on W32 systems) by means of the Registry entry


              Outputs additional information while running.  You can  increase
              the  verbosity by giving several verbose commands to gpgsm, such
              as '-vv'.

       --debug-level level
              Select the debug level for investigating problems.  level may be
              a numeric value or a keyword:

              none   No  debugging at all.  A value of less than 1 may be used
                     instead of the keyword.

              basic  Some basic debug messages.  A value between 1 and  2  may
                     be used instead of the keyword.

                     More verbose debug messages.  A value between 3 and 5 may
                     be used instead of the keyword.

              expert Even more detailed messages.  A value between 6 and 8 may
                     be used instead of the keyword.

              guru   All  of  the  debug messages you can get. A value greater
                     than 8 may be used instead of the keyword.  The  creation
                     of  hash  tracing files is only enabled if the keyword is

       How these messages are mapped to the  actual  debugging  flags  is  not
       specified  and may change with newer releases of this program. They are
       however carefully selected to best aid in debugging.

              All debugging options are subject to change and thus should  not
              be  used by any application program.  As the name says, they are
              only used as helpers to debug problems.

       --debug flags
              This option is only useful for debugging and the  behaviour  may
              change  at  any  time without notice.  FLAGS are bit encoded and
              may be given in usual C-Syntax. The currently defined bits are:

              0 (1)  command I/O

              1 (2)  values of big number integers

              2 (4)  low level crypto operations

              5 (32) memory allocation

              6 (64) caching

              7 (128)
                     show memory statistics.

              9 (512)
                     write hashed data to files named dbgmd-000*

              10 (1024)
                     trace Assuan protocol.  See also  option  --debug-assuan-

              11 (2048)
                     trace  APDU  I/O  to the card.  This may reveal sensitive

              12 (4096)
                     trace some card reader related function calls.

              Same as --debug=0xffffffff

       --debug-wait n
              When running in server mode, wait n seconds before entering  the
              actual  processing  loop  and print the pid.  This gives time to
              attach a debugger.

              Enable debug output from the included  CCID  driver  for  smart-
              cards.  Using this option twice will also enable some tracing of
              the T=1 protocol.  Note that this option  may  reveal  sensitive

              This option disables all ticker functions like checking for card

              For security reasons we  won't  create  a  core  dump  when  the
              process  aborts.   For debugging purposes it is sometimes better
              to allow core dump.  This options enables it  and  also  changes
              the working directory to `/tmp' when running in --server mode.

              This option appends a thread ID to the PID in the log output.

       --debug-assuan-log-cats cats
              Changes  the  active  Libassuan logging categories to cats.  The
              value for cats is an unsigned integer given in  usual  C-Syntax.
              A  value of of 0 switches to a default category.  If this option
              is not used the categories are taken from the environment  vari-
              able  'ASSUAN_DEBUG'.   Note that this option has only an effect
              if the Assuan debug flag has also been with the option  --debug.
              For a list of categories see the Libassuan manual.

              Don't  detach the process from the console.  This is mainly use-
              ful for debugging.

       --log-file file
              Append all logging output to file.  This is very helpful in see-
              ing what the agent actually does.

       --pcsc-driver library
              Use library to access the smartcard reader.  The current default
              is `libpcsclite.so'.  Instead of using  this  option  you  might
              also  want  to  install a symbolic link to the default file name
              (e.g. from `libpcsclite.so.1').

       --ctapi-driver library
              Use library to access the smartcard reader.  The current default
              is  `libtowitoko.so'.   Note  that  the use of this interface is
              deprecated; it may be removed in future releases.

              Disable the integrated support for CCID compliant readers.  This
              allows  to  fall  back  to  one of the other drivers even if the
              internal CCID driver can handle the  reader.   Note,  that  CCID
              support is only available if libusb was available at build time.

       --reader-port number_or_string
              This  option  may be used to specify the port of the card termi-
              nal.  A value of 0 refers to the first serial device; add  32768
              to access USB devices.  The default is 32768 (first USB device).
              PC/SC or CCID readers might need a string here; run the  program
              in verbose mode to get a list of available readers.  The default
              is then the first reader found.

              To get a list of available CCID readers you may  use  this  com-
         echo scd getinfo reader_list | gpg-connect-agent --decode | awk '/^D/ {print $2}'

       --card-timeout n
              If n is not 0 and no client is actively using the card, the card
              will be powered down after n seconds.  Powering  down  the  card
              avoids  a  potential risk of damaging a card when used with cer-
              tain cheap readers.  This also allows non Scdaemon aware  appli-
              cations  to  access  the card.  The disadvantage of using a card
              timeout is that accessing the card takes  longer  and  that  the
              user needs to enter the PIN again after the next power up.

              Note  that with the current version of Scdaemon the card is pow-
              ered down immediately at the next timer tick for any value of  n
              other than 0.

              Please  specify  this option when the card reader supports vari-
              able length input for pinpad (default is no).  For known readers
              (listed in ccid-driver.c and apdu.c), this option is not needed.
              Note that if your card reader doesn't supports  variable  length
              input  but  you  want to use it, you need to specify your pinpad
              request on your card.

              Even if a card reader features a pinpad, do not try to use it.

              This option disables the use of admin class  commands  for  card
              applications  where  this is supported.  Currently we support it
              for the OpenPGP card. This commands is useful to  inhibit  acci-
              dental access to admin class command which could ultimately lock
              the card through wrong PIN numbers.  Note  that  GnuPG  versions
              older  than  2.0.11  featured an --allow-admin command which was
              required to use such admin commands.  This option  has  no  more
              effect today because the default is now to allow admin commands.

       --disable-application name
              This option disables the use of the card application named name.
              This is mainly useful for debugging or  if  a  application  with
              lower priority should be used by default.

              All the long options may also be given in the configuration file
              after stripping off the two leading dashes.

       scdaemon supports the card applications as described below.

   The OpenPGP card application ``openpgp''

       This application is currently only used by gpg but may in  future  also
       be  useful  with  gpgsm.   Version  1 and version 2 of the card is sup-

       The   specifications    for    these    cards    are    available    at
       (http://g10code.com/docs/openpgp-card-1.0.pdf)                      and

   The Telesec NetKey card ``nks''

       This is the main application of the Telesec cards as available in  Ger-
       many.  It is a superset of the German DINSIG card.  The card is used by

   The DINSIG card application ``dinsig''

       This is an application as described in the German draft standard DIN  V
       66291-1.  It is intended to be used by cards supporting the German sig-
       nature law and its bylaws (SigG and SigV).

   The PKCS#15 card application ``p15''

       This is common framework for smart card applications.  It  is  used  by

   The Geldkarte card application ``geldkarte''

       This  is  a simple application to display information of a German Geld-
       karte.  The Geldkarte is a small amount debit  card  application  which
       comes with almost all German banking cards.

   The Undefined card application ``undefined''

       This is a stub application to allow the use of the APDU command even if
       no supported application is found on the card.  This application is not
       used  automatically but must be explicitly requested using the SERIALNO

         $ scdaemon --server -v

       There are a few configuration  files  to  control  certain  aspects  of
       scdaemons's  operation.  Unless noted, they are expected in the current
       home directory (see: [option --homedir]).

              This is the standard configuration  file  read  by  scdaemon  on
              startup.   It may contain any valid long option; the leading two
              dashes may not be entered and the option may not be abbreviated.
              This  default  name  may  be  changed  on the command line (see:
              [option --options]).

              If this file is present and executable, it  will  be  called  on
              veyer card reader's status changed. An example of this script is
              provided with the distribution

              This file is created by sdaemon to let  other  applications  now
              about reader status changes.  Its use is now deprecated in favor
              of `scd-event'.

       See attributes(5) for descriptions of the following attributes:

       |Availability   | crypto/gnupg     |
       |Stability      | Uncommitted      |
       gpg-agent(1), gpgsm(1), gpg2(1)

       The full documentation for this tool is maintained as a Texinfo manual.
       If  GnuPG and the info program are properly installed at your site, the

         info gnupg

       should give you access to the complete manual including a  menu  struc-
       ture and an index.

       This     software     was    built    from    source    available    at
       https://java.net/projects/solaris-userland.   The  original   community
       source                was                downloaded                from

       Further information about this software can be found on the open source
       community website at http://www.gnupg.org/.

GnuPG 2.0.27                      2015-08-20                       SCDAEMON(1)