strconf(1)

NAME

     strchg, strconf - change or query stream configuration

SYNOPSIS

     strchg -h module1 [ , module2...]

     strchg -p [-a | -u module]

     strchg -f filename

     strconf [-m | -t module]

DESCRIPTION

     These commands are used to alter or query the  configuration
     of the stream associated with the user's standard input. The
     strchg command pushes modules on and/or pops modules off the
     stream. The strconf command queries the configuration of the
     stream. Only the super-user or owner of a STREAMS device may
     alter the configuration of that stream.

     Invoked without any arguments, strconf prints a list of  all
     the modules in the stream as well as the topmost driver. The
     list is printed with one name per line where the first  name
     printed  is the topmost module on the stream (if one exists)
     and the last item printed is the name of the driver.

OPTIONS

     The following options apply to strchg and, -h,  -f,  and  -p
     are mutually exclusive.

     -h module1 [,module2...]
            Mnemonic for push, pushes modules onto a  stream.  It
           takes  as  arguments the names of one or more pushable
           streams modules. These modules are  pushed  in  order;
           that  is,  module1  is pushed first, module2 is pushed
           second, etc.

     -p    Mnemonic for pop, pops modules off  the  stream.  With
           the  -p  option  alone, strchg pops the topmost module
           from the stream.

     -a module
           Pop all the modules above the topmost driver  off  the
           stream. This option requires the -p option.

     -u module
           All modules above, but not including module are popped
           off the stream. This option requires the -p option.

     -f filename
           Specify a filename that contains  a  list  of  modules
           representing  the desired configuration of the stream.
           Each module name must appear on a separate line  where
           the  first  name represents the topmost module and the
           last name represents the module that should be closest
           to  the driver. strchg will determine the current con-
           figuration of the stream and pop and push  the  neces-
           sary  modules in order to end up with the desired con-
           figuration.

     The following options apply to strconf and, -m  and  -t  are
     mutually exclusive.

     -m module
           Determine if the named module is present on a  stream.
           If  it  is, strconf prints the message yes and returns
           zero. If  not,  strconf  prints  the  message  no  and
           returns  a  non-zero  value. The -t and -m options are
           mutually exclusive.

     -t module
           Print only the topmost module (if one exists). The  -t
           and -m options are mutually exclusive.

EXAMPLES

     Example 1: Using the strchg Command

     The following command pushes the module ldterm on the stream
     associated with the user's standard input:

     example% strchg -h ldterm

     The following command  pops  the  topmost  module  from  the
     stream  associated  with  /dev/term/24. The user must be the
     owner of this device or the super user.

     example% strchg -p < /dev/term/24

     If the file fileconf contains the following:

     ttcompat
     ldterm
     ptem

     then the command

     example% strchg -f fileconf
     will configure the user's standard input stream so that  the
     module  ptem  is  pushed over the driver, followed by ldterm
     and ttcompat closest to the stream head.

     The strconf command with no arguments lists the modules  and
     topmost driver on the stream; for a stream that has only the
     module ldterm pushed above the zs driver, it  would  produce
     the following output:

     ldterm
     zs

     The following command asks if ldterm is on the stream:

     example% strconf -m ldterm

     and produces the following output while  returning  an  exit
     status of 0:

     yes

ATTRIBUTES

     See attributes(5) for descriptions of the  following  attri-
     butes:

     ____________________________________________________________
    |       ATTRIBUTE TYPE        |       ATTRIBUTE VALUE       |
    | Availability                | SUNWcsu                     |
    |_____________________________|_____________________________|

SEE ALSO

     attributes(5), streamio(7I)

DIAGNOSTICS

     strchg returns zero on success. It prints an  error  message
     and  returns  non-zero  status for various error conditions,
     including usage error, bad module name, too many modules  to
     push,  failure of an ioctl on the stream, or failure to open
     filename from the -f option.

     strconf returns zero on success (for the -m  or  -t  option,
     "success"  means the named or topmost module is present). It
     returns a non-zero status if  invoked  with  the  -m  or  -t
     option  and  the  module  is not present. It prints an error
     message and returns non-zero status for various error condi-
     tions,  including  usage error or failure of an ioctl on the
     stream.

NOTES

     If the user is neither the  owner  of  the  stream  nor  the
     super-user,  the  strchg command will fail. If the user does
     not have read permissions on the stream and is not the super
     user, the strconf command will fail.

     If modules are pushed in the wrong order, one could  end  up
     with  a stream that does not function as expected. For ttys,
     if the line discipline module is not pushed in  the  correct
     place,  one  could  have a terminal that does not respond to
     any commands.