Provided by: expect_5.45.4-2_amd64 bug

NAME

       autoexpect - generate an Expect script from watching a session

SYNOPSIS

       autoexpect [ args ] [ program args...  ]

INTRODUCTION

       autoexpect  watches you interacting with another program and creates an Expect script that
       reproduces your interactions.  For straightline scripts, autoexpect saves substantial time
       over  writing  scripts  by  hand.   Even  if  you  are  an Expect expert, you will find it
       convenient to use autoexpect to automate the more mindless parts of interactions.   It  is
       much  easier  to  cut/paste  hunks  of autoexpect scripts together than to write them from
       scratch.  And if you are a beginner, you may be able to get  away  with  learning  nothing
       more about Expect than how to call autoexpect.

       The  simplest way to use autoexpect is to call it from the command line with no arguments.
       For example:

            % autoexpect

       By default, autoexpect spawns a shell for  you.   Given  a  program  name  and  arguments,
       autoexpect spawns that program.  For example:

            % autoexpect ftp ftp.cme.nist.gov

       Once  your  spawned program is running, interact normally.  When you have exited the shell
       (or program that you specified), autoexpect will create a new script for you.  By default,
       autoexpect  writes the new script to "script.exp".  You can override this with the -f flag
       followed by a new script name.

       The following example runs "ftp ftp.cme.nist.gov" and stores the resulting  Expect  script
       in the file "nist".

            % autoexpect -f nist ftp ftp.cme.nist.gov

       It  is important to understand that autoexpect does not guarantee a working script because
       it necessarily has to guess about certain things -  and  occasionally  it  guesses  wrong.
       However, it is usually very easy to identify and fix these problems.  The typical problems
       are:

              ·   Timing.  A surprisingly large number of programs (rn, ksh, zsh,  telnet,  etc.)
                  and  devices  (e.g.,  modems) ignore keystrokes that arrive "too quickly" after
                  prompts.  If you find your new script hanging up at  one  spot,  try  adding  a
                  short sleep just before the previous send.

                  You   can   force   this   behavior   throughout  by  overriding  the  variable
                  "force_conservative"  near  the  beginning  of  the  generated  script.    This
                  "conservative"  mode makes autoexpect automatically pause briefly (one tenth of
                  a second) before sending each character.  This pacifies every  program  I  know
                  of.

                  This  conservative mode is useful if you just want to quickly reassure yourself
                  that the problem is a timing one (or if you really don't care  about  how  fast
                  the  script  runs).   This  same mode can be forced before script generation by
                  using the -c flag.

                  Fortunately,  these  timing  spots  are  rare.   For  example,  telnet  ignores
                  characters  only  after  entering  its  escape  sequence.   Modems  only ignore
                  characters immediately after connecting to them for  the  first  time.   A  few
                  programs  exhibit  this  behavior  all  the time but typically have a switch to
                  disable it.  For example, rn's -T flag disables this behavior.

                  The following example starts autoexpect in conservative mode.

                       autoexpect -c

                  The -C flag defines a key to toggle conservative mode.  The  following  example
                  starts autoexpect (in non-conservative mode) with ^L as the toggle.  (Note that
                  the ^L is entered literally - i.e., enter a real control-L).

                       autoexpect -C ^L

                  The following example starts autoexpect in conservative mode  with  ^L  as  the
                  toggle.

                       autoexpect -c -C ^L

              ·   Echoing.   Many  program echo characters.  For example, if you type "more" to a
                  shell, what autoexpect actually sees is:

                       you typed 'm',
                       computer typed 'm',
                       you typed 'o',
                       computer typed 'o',
                       you typed 'r',
                       computer typed 'r',
                       ...

                  Without specific knowledge of the program, it is impossible to know if you  are
                  waiting  to  see  each  character echoed before typing the next.  If autoexpect
                  sees characters being echoed, it assumes that it can send them all as  a  group
                  rather than interleaving them the way they originally appeared.  This makes the
                  script more pleasant to read.  However, it could conceivably  be  incorrect  if
                  you really had to wait to see each character echoed.

              ·   Change.  Autoexpect records every character from the interaction in the script.
                  This is desirable because it gives you the ability  to  make  judgements  about
                  what is important and what can be replaced with a pattern match.

                  On  the  other  hand, if you use commands whose output differs from run to run,
                  the generated scripts are not going to be correct.   For  example,  the  "date"
                  command  always  produces  different  output.   So using the date command while
                  running autoexpect is a sure way to produce a script that will require  editing
                  in order for it to work.

                  The  -p flag puts autoexpect into "prompt mode".  In this mode, autoexpect will
                  only look for the the last line of  program  output  -  which  is  usually  the
                  prompt.  This handles the date problem (see above) and most others.

                  The following example starts autoexpect in prompt mode.

                       autoexpect -p

                  The  -P flag defines a key to toggle prompt mode.  The following example starts
                  autoexpect (in non-prompt mode) with ^P as the toggle.  Note  that  the  ^P  is
                  entered literally - i.e., enter a real control-P.

                       autoexpect -P ^P

                  The following example starts autoexpect in prompt mode with ^P as the toggle.

                       autoexpect -p -P ^P

OTHER FLAGS

       The -quiet flag disables informational messages produced by autoexpect.

       The  -Q flag names a quote character which can be used to enter characters that autoexpect
       would otherwise consume because they are used as toggles.

       The following example shows a number of flags with quote used to provide a way of entering
       the toggles literally.

            autoexpect -P ^P -C ^L -Q ^Q

STYLE

       I  don't  know  if there is a "style" for Expect programs but autoexpect should definitely
       not be held up as any model of style.  For example, autoexpect  uses  features  of  Expect
       that  are  intended  specifically  for  computer-generated  scripting.   So  don't  try to
       faithfully write scripts that appear as if they were generated by autoexpect.  This is not
       useful.

       On  the  other  hand, autoexpect scripts do show some worthwhile things.  For example, you
       can see how any string must be quoted in order to use it in a Tcl script simply by running
       the strings through autoexpect.

SEE ALSO

       "Exploring  Expect: A Tcl-Based Toolkit for Automating Interactive Programs" by Don Libes,
       O'Reilly and Associates, January 1995.

AUTHOR

       Don Libes, National Institute of Standards and Technology

       expect and autoexpect are in the public domain.  NIST and I  would  appreciate  credit  if
       these programs or parts of them are used.

                                           30 June 1995                             AUTOEXPECT(1)