ttsession(1) ToolTalk Commands ttsession(1)NAMEttsession - the ToolTalk message server
SYNOPSISttsession [−hNpsStv] [−E⎪−X] [−a level] [−d display] [−c [command]]
DESCRIPTION
The ttsession utility is the ToolTalk message server. This background
process must be running before any messages can be sent or received.
Each message server defines a session.
The message server has no user interface and typically runs in the
background, started either by the user's .xinitrc file or automatically
by any program that needs to send or receive a message.
OPTIONS
The following options are available:
−a level
Set the server authentication level. The following level
string values are supported:
unix The sender and receiver must have the same user ID.
des The underlying RPC calls use AUTH_DES.
gss The underlying RPC calls use RPCSEC_GSS.
For gss, additional options may be specified after
an immediately following comma in a comma separated
(without spaces) list of suboptions and keyword-
attribute pairs:
protect={access,integrity,privacy}
Specify the GSS service type. If no service
type is specified, protect=access is assumed.
protect=access
means the GSS mechanism is used to verify
that clients have the credentials of the
user that started ttsession.
protect=integrity
means the GSS mechanism is used to verify
integrity of the data transmitted between
ttsession and its clients. pro‐
tect=integrity implies protect=access
protect=privacy
means the Gss mechanism is used to pro‐
vide privacy against the data transmitted
between ttsession and its clients. pro‐
tect=integrity implies protect=access.
mechanism=<mechanism name>
Use the named security mechanism. If no mecha‐
nism is specifierd, ttsession wil arbitrarily
choose one of the installed mechanisms
qop=<quality of protection>
Use the named quality of protection. If the
quality of protection is not specified, the
default for the mechanism is used.
EXAMPLE
To specify GSS authentication using the kerberos_v5 mecha‐
nism and the GSS_KRB5_CONF_C_QOP_DES quality of protection,
start ttsession as:
ttsession-a gss,mechanism=kerberos_v5,qop=GSS_KRB5_CONF_C_QOP_DES
This assumes that the kerberos_v5 mechanism is installed.
Security options can be overridden on a systemwide basis
via the file /etc/default/ttsession (ttsession_file(4)).
−c [command]
Start a process tree session and run the given command.
The ttsession utility sets the environment variable TT_SES‐
SION to the name of this session. Any process started with
this variable in the environment defaults to being in this
session. If command is omitted, ttsession invokes the
shell named by the SHELL environment variable. Everything
after −c on the command line is used as the command to be
executed.
−d display
Specify an X Windows display. The ToolTalk session will
consist of those applications displaying on the named dis‐
play. The default display is identified by the DISPLAY
environment variable.
−E Read in the types from the Classing Engine database. If
neither −E nor −X is given, −X is assumed.
−h Write a help message to standard error that describes the
command syntax of ttsession, and exit.
−N Maximize the number of clients allowed to connect to (in
other words, open procids in) this session by attempting to
raise the limit of open file descriptors. The precise num‐
ber of clients is system-dependent; on some systems this
option may have no effect. On Solaris 2.6 and later,
ttsession always maximizes the number of clients, so there
is no need to specify this option.
−o allow_unauth_types_load=<yes|no>
By default calls to tt_session_types_load(3) in the
ToolTalk API will fail with TT_ERR_ACCESS. The system wide
default in this regard may be changed via ttses‐
sion_file(4). The behavior for a particular ttsession may
be changed via this option, if and only if the ttses‐
sion_file(4) has not "locked" per-ttsession changes to this
option.
-p Write the name of a new process tree session to standard
output, and then fork a background instance of ttsession to
manage this new session.
−s Silent. Do not write any warning messages to standard
error.
−S Do not fork a background instance to manage the ttsession
session.
−t Turn on trace mode. See ASYNCHRONOUS EVENTS for how to
turn tracing on and off during execution. Tracing displays
the state of a message when it is first seen by ttsession.
The lifetime of the message is then shown by showing the
result of matching the message against type signatures
(dispatch stage) and then showing the result of matching
the message against any registered message patterns (deliv‐
ery stage). Any attempt to send the message to a given
process is also shown together with the success of that
attempt.
−v Write the version number to standard output and exit.
−X Read in the types from the XDR format databases. (Default)
OPERANDS
None.
STDIN
Not used.
INPUT FILES
The XDR format databases listed by the −X option are serialized
ToolTalk data structures of an unspecified format, except that it is
the same as the format of tt_type_comp(1) output files.
The file /etc/default/ttsession (ttsession_file(4)) can be used to
change the system-wide behavior of the ttsession process depending on
the contents of the file.
ENVIRONMENT VARIABLES
The following environment variables affect the execution of ttsession:
CEPATH In Classing Engine mode, this variable tells the
Classing Engine where to find the databases that con‐
tain ToolTalk types. See ce_db_build(1).
DISPLAY If TT_SESSION is not set and DISPLAY is set, then the
value of DISPLAY will be used by all ToolTalk clients
to identify the ttsession process serving their X
display. If no such process is running, the ToolTalk
service will auto-start one.
If ttsession is run with the −d option and DISPLAY is
not set, ttsession sets DISPLAY to be the value of
the −d option for itself and all processes it forks.
This helps ToolTalk clients to find the right X dis‐
play when they are auto-started by ttsession.
LANG Provide a default value for the internationalization
variables that are unset or null. If LANG is unset
or null, the corresponding value from the implementa‐
tion-specific default locale will be used. If any of
the internationalization variables contains an
invalid setting, the utility behaves as if none of
the variables had been defined.
LC_ALL If set to a non-empty string value, override the val‐
ues of all the other internationalization variables.
LC_MESSAGES Determine the locale that is used to affect the for‐
mat and contents of diagnostic messages written to
standard error and informative messages written to
standard output.
NLSPATH Determine the location of message catalogues for the
processing of LC_MESSAGES.
TT_ARG_TRACE_WIDTH
Specify the number of bytes of argument and context
values to write when in trace mode. The default is
to print the first 40 bytes.
TTPATH In XDR mode, a colon-separated list of directories
that tells ToolTalk where to find the ToolTalk types
databases. See tt_type_comp(1).
TTSESSION_CMD
Specify the shell command to be used by all ToolTalk
clients for auto-starting ttsession.
The ttsession utility creates the following variable when it invokes
another process:
TT_FILE When ttsession invokes a tool to receive a message,
it copies the file attribute (if any) of the message
into this variable, formatted in the same manner as
returned by the tt_message_file(3) function.
TT_SESSION The ttsession utility uses this variable to communi‐
cate its session ID to the tools that it starts. The
format of the variable is implementation specific.
If this variable is set, the ToolTalk client library
uses its value as the default session ID.
TT_TOKEN Inform the ToolTalk client library that it has been
invoked by ttsession, so that the client can confirm
to ttsession that it started successfully. The for‐
mat of the variable is implementation specific.
A tool started by ttsession must ensure that the TT_SESSION and
TT_TOKEN are present in the environment of any processes it invokes.
RESOURCES
None.
ASYNCHRONOUS EVENTS
The ttsession utility reacts to two signals. If it receives the
SIGUSR1 signal, it toggles trace mode on or off (see the −t option).
If it receives the SIGUSR2 signal, it rereads the types file. The
ttsession utility takes the standard action for all other signals.
STDOUT
When the −v option is used, ttsession writes the version number in an
unspecified format. When −p is used, ttsession writes the name of a
new process tree session.
STDERR
Used only for diagnostic messages and the help message written by the
−h option.
OUTPUT FILES
None.
EXTENDED DESCRIPTION
None.
EXIT STATUS
When the −c child process exits, ttsession exits with the status of the
exited child. Otherwise, the following exit values are returned:
0 Normal termination. Without the −c or −S options, a zero exit
status means ttsession has successfully forked an instance of
itself that has begun serving the session.
1 Abnormal termination. The ttsession utility was given invalid
command line options, was interrupted by SIGINT, or encountered
some internal error.
2 Collision. Another ttsession was found to be serving the ses‐
sion already.
CONSEQUENCES OF ERRORS
The ttsession utility takes the standard action for all signals.
APPLICATION USAGE
Since everything after −c on the command line is used as the command to
be executed, −c should be the last option.
Tracing is helpful for seeing how messages are dispatched and deliv‐
ered, but the output may be voluminous.
EXAMPLES
None.
SEE ALSOtt_type_comp(1), tttrace(1), tt_message_file(3), ttsession_file(4).
ToolTalk 1.3 1 March 1996 ttsession(1)
