NAME

     ikp_tee - icon processing system tee implementation

SYNOPSIS

     ikp_tee [ -b bufsize ] [ -f [ -d tmpdir ] ]

DESCRIPTION

     ikp_tee implements the tee processes of the ikp(1) icon pro-
     cessing  interface by reading input on file descriptor 0 and
     copying it unchanged onto  file  descriptors  3  and  4.  It
     should  only  be  invoked indirectly by ikp on behalf of the
     user.

     It normally works by reading its input one buffer at a time.
     As  each  buffer  is read, it is written first to one output
     stream and then to the other. If either output stream blocks
     for  any  reason,  the entire tee will block. This scheme is
     fairly efficient in terms of its minimal memory  usage,  but
     may  cause fatal deadlock in more complicated networks, par-
     ticularly those which cause both output streams from  a  tee
     to  be  later  merged  via  a process such as ikp_cat(1). To
     alleviate this problem, an  alternative  mode  of  operation
     employing  a  temporary  file  and non-blocking I/O has been
     provided.  Note that this latter scheme cannot  be  used  if
     the  tee is embedded in a process loop, since it attempts to
     read all of its input and save it to a temporary file before
     any output is written.

OPTIONS

     -b bufsize
          Perform all I/O with an  internal  buffer  of  bufsize.
          (The default buffer size is 512.)

     -f   Use a temporary file and non-blocking I/O to  implement
          the tee instead of the default blocking I/O scheme.

     -d tmpdir
          Use tmpdir instead of /tmp to hold the  temporary  file
          created by using the -f option.

BUGS

     This utility should be rewritten  with  a  single  algorithm
     which  will work under all circumstances and not require the
     user to decide which of the two current implementations will
     work best in a particular context.

SEE ALSO

     ikp(1)

AUTHOR

     Roger Davis, October 1989.

COPYRIGHT

     copyright 2001, Amoco Production Company
               All Rights Reserved
          an affiliate of BP America Inc.