библиотека программных диалогов с интерактивными программами  (programmed dialogue library with interactive programs)
  
LOGGING
extern int exp_loguser;
       extern int exp_logfile_all
       extern FILE *exp_logfile;
       If exp_loguser is nonzero, expect sends any output from the
       spawned process to stdout.  Since interactive programs typically
       echo their input, this usually suffices to show both sides of the
       conversation.  If exp_logfile is also nonzero, this same output
       is written to the stream defined by exp_logfile.  If
       exp_logfile_all is non-zero, exp_logfile is written regardless of
       the value of exp_loguser.