URL https://opencores.org/ocsvn/openrisc_2011-10-31/openrisc_2011-10-31/trunk
Subversion Repositories openrisc_2011-10-31

[/] [openrisc/] [trunk/] [rtos/] [rtems/] [c/] [src/] [libnetworking/] [pppd/] [chat.c] - Blame information for rev 173

Details | Compare with Previous | View Log

/*
 *      Chat -- a program for automatic session establishment (i.e. dial
 *              the phone and log in).
 *
 * Standard termination codes:
 *  0 - successful completion of the script
 *  1 - invalid argument, expect string too large, etc.
 *  2 - error on an I/O operation or fatal error condition.
 *  3 - timeout waiting for a simple string.
 *  4 - the first string declared as "ABORT"
 *  5 - the second string declared as "ABORT"
 *  6 - ... and so on for successive ABORT strings.
 *
 *      This software is in the public domain.
 *
 * -----------------
 *      added -T and -U option and \T and \U substitution to pass a phone
 *      number into chat script. Two are needed for some ISDN TA applications.
 *      Keith Dart <kdart@cisco.com>
 *
 *
 *      Added SAY keyword to send output to stderr.
 *      This allows to turn ECHO OFF and to output specific, user selected,
 *      text to give progress messages. This best works when stderr
 *      exists (i.e.: pppd in nodetach mode).
 *
 *      Added HANGUP directives to allow for us to be called
 *      back. When HANGUP is set to NO, chat will not hangup at HUP signal.
 *      We rely on timeouts in that case.
 *
 *      Added CLR_ABORT to clear previously set ABORT string. This has been
 *      dictated by the HANGUP above as "NO CARRIER" (for example) must be
 *      an ABORT condition until we know the other host is going to close
 *      the connection for call back. As soon as we have completed the
 *      first stage of the call back sequence, "NO CARRIER" is a valid, non
 *      fatal string. As soon as we got called back (probably get "CONNECT"),
 *      we should re-arm the ABORT "NO CARRIER". Hence the CLR_ABORT command.
 *      Note that CLR_ABORT packs the abort_strings[] array so that we do not
 *      have unused entries not being reclaimed.
 *
 *      In the same vein as above, added CLR_REPORT keyword.
 *
 *      Allow for comments. Line starting with '#' are comments and are
 *      ignored. If a '#' is to be expected as the first character, the
 *      expect string must be quoted.
 *
 *
 *              Francis Demierre <Francis@SwissMail.Com>
 *              Thu May 15 17:15:40 MET DST 1997
 *
 *
 *      Added -r "report file" switch & REPORT keyword.
 *              Robert Geer <bgeer@xmission.com>
 *
 *      Added -s "use stderr" and -S "don't use syslog" switches.
 *              June 18, 1997
 *              Karl O. Pinc <kop@meme.com>
 *
 *
 *      Added -e "echo" switch & ECHO keyword
 *              Dick Streefland <dicks@tasking.nl>
 *
 *
 *      Considerable updates and modifications by
 *              Al Longyear <longyear@pobox.com>
 *              Paul Mackerras <paulus@cs.anu.edu.au>
 *
 *
 *      The original author is:
 *
 *              Karl Fox <karl@MorningStar.Com>
 *              Morning Star Technologies, Inc.
 *              1760 Zollinger Road
 *              Columbus, OH  43221
 *              (614)451-1883
 *
 *
 */
 
#ifndef lint
/* static char rcsid[] = ""; */
#endif
 
#include <stdio.h>
#include <ctype.h>
#include <time.h>
#include <fcntl.h>
#include <signal.h>
#include <errno.h>
#include <string.h>
#include <stdlib.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <syslog.h>
 
#undef  TERMIOS
#define TERMIOS
 
 
#include <termios.h>
 
#define STR_LEN 1024
char temp2[STR_LEN];
 
#ifndef SIGTYPE
#define SIGTYPE void
#endif
 
#undef __P
#undef __V
 
#ifdef __STDC__
#include <stdarg.h>
#define __V(x)  x
#define __P(x)  x
#else
#include <varargs.h>
#define __V(x)  (va_alist) va_dcl
#define __P(x)  ()
#define const
#endif
 
#ifndef O_NONBLOCK
#define O_NONBLOCK      O_NDELAY
#endif
 
 
/*************** Micro getopt() *********************************************/
#define OPTION(c,v)     (_O&2&&**v?*(*v)++:!c||_O&4?0:(!(_O&1)&& \
                                (--c,++v),_O=4,c&&**v=='-'&&v[0][1]?*++*v=='-'\
                                &&!v[0][1]?(--c,++v,0):(_O=2,*(*v)++):0))
#define OPTARG(c,v)     (_O&2?**v||(++v,--c)?(_O=1,--c,*v++): \
                                (_O=4,(char*)0):(char*)0)
#define OPTONLYARG(c,v) (_O&2&&**v?(_O=1,--c,*v++):(char*)0)
#define ARG(c,v)        (c?(--c,*v++):(char*)0)
 
#if 0
static int _O = 0;               /* Internal state */
#endif
/*************** Micro getopt() *********************************************/
 
char *program_name;
 
#define MAX_ABORTS              5
#define MAX_REPORTS             5
#define DEFAULT_CHAT_TIMEOUT    45
#define fcntl(a, b,c ) 0
#define MAX_TIMEOUTS 10
 
int echo          = 0;
int verbose       = 0;
int to_log        = 1;
int to_stderr     = 0;
int Verbose       = 0;
int quiet         = 0;
int report        = 0;
int exit_code     = 0;
static int speed=0;
char *report_file = (char *) 0;
char *chat_file   = (char *) 0;
char *phone_num   = (char *) 0;
char *phone_num2  = (char *) 0;
int chat_timeout       = DEFAULT_CHAT_TIMEOUT;
static int timeout       = DEFAULT_CHAT_TIMEOUT;
int have_tty_parameters = 0;
 
#ifdef TERMIOS
#define term_parms struct termios
#define get_term_param(param) tcgetattr(modem_fd, param)
#define set_term_param(param) tcsetattr(modem_fd, TCSANOW, param)
struct termios saved_tty_parameters;
#endif
 
char *abort_string[MAX_ABORTS]={"BUSY","NO DIALTONE","NO CARRIER","NO ASWER","RINGING\r\n\r\nRINGING"};
char *fail_reason = (char *)0,
        fail_buffer[50];
int n_aborts = MAX_ABORTS, abort_next = 0, timeout_next = 0, echo_next = 0;
int clear_abort_next = 0;
 
char *report_string[MAX_REPORTS] ;
char  report_buffer[50] ;
int n_reports = 0, report_next = 0, report_gathering = 0 ;
int clear_report_next = 0;
 
int say_next = 0, hup_next = 0;
 
void *dup_mem __P((void *b, size_t c));
void *copy_of __P((char *s));
/*
SIGTYPE sigalrm __P((int signo));
SIGTYPE sigint __P((int signo));
SIGTYPE sigterm __P((int signo));
SIGTYPE sighup __P((int signo));
*/
void unalarm __P((void));
void init __P((void));
void set_tty_parameters __P((void));
void echo_stderr __P((int));
void break_sequence __P((void));
void terminate __P((int status));
void do_file __P((char *chat_file));
int  get_string __P((register char *string));
int  put_string __P((register char *s));
int  write_char __P((int c));
int  put_char __P((int c));
int  get_char __P((void));
void chat_send __P((register char *s));
char *character __P((int c));
void chat_expect __P((register char *s));
char *clean __P((register char *s, int sending));
void break_sequence __P((void));
void terminate __P((int status));
void pack_array __P((char **array, int end));
char *expect_strtok __P((char *, char *));
int vfmtmsg __P((char *, int, const char *, va_list));  /* vsprintf++ */
 
#if 0
int usleep( long usec );                                  /* returns 0 if ok, else -1 */
#endif
 
extern int input_fd,output_fd;
 
int main __P((int, char *[]));
 
void *dup_mem(b, c)
void *b;
size_t c;
{
    void *ans = malloc (c);
    if (!ans)
                return NULL;
 
    memcpy (ans, b, c);
    return ans;
}
 
void *copy_of (s)
char *s;
{
    return dup_mem (s, strlen (s) + 1);
}
 
/*
 * chat [ -v ] [-T number] [-U number] [ -t timeout ] [ -f chat-file ] \
 * [ -r report-file ] \
 *              [...[[expect[-say[-expect...]] say expect[-say[-expect]] ...]]]
 *
 *      Perform a UUCP-dialer-like chat script on stdin and stdout.
 */
char *getnextcommand(char **string)
{
        char *buf=*string,*res;
        res=strchr(buf,'@');
        if (res==NULL)
                return NULL;
        *res='\0';
        *string=res+1;
        return buf;
}
 
 
extern int modem_fd;
int
        chatmain(argv)
     char *argv;
{
    char *arg;
        int i;
        char *t;
        exit_code=0;
        speed=0;
/*
 * Default the report file to the stderr location
 */
/*    if (report_fp == NULL)
        report_fp = stderr;
*/
    init();
        while ( (arg = getnextcommand(&argv)) != NULL) {
            chat_expect(arg);
                if (exit_code>0) break;
            t=temp2;
 
                while(*t)
                {
                        if (strncmp("CARRIER",t,7)==0)
                        {/* parse speed information */
                                i=0;
                                while(!isdigit(t[i]))
                                        i++;
                                t=&t[i];
                                i=0;
                                while(isdigit(t[i]))
                                        i++;
                                t[i]=0;
                                sscanf(t,"%d",&speed);
                                break;
                        }
                        t++;
                }
            if ((arg = getnextcommand(&argv)) != NULL)
                chat_send(arg);
                if (exit_code>0) break;
        }
 
    if (exit_code) return exit_code;
    return -speed;
}
 
 
 
/*
 *      Print an error message and terminate.
 */
 
void init()
{
    set_tty_parameters();
        speed=0;
}
 
void set_tty_parameters()
{
    term_parms t;
 
        if (get_term_param (&t) < 0)
                syslog(LOG_NOTICE,"Can't get terminal parameters:")
                ;
 
    saved_tty_parameters = t;
    have_tty_parameters  = 1;
    t.c_iflag     |= IGNBRK | ISTRIP | IGNPAR;
    t.c_oflag      = 0;
    t.c_lflag      = 0;
    t.c_cc[VERASE] =
    t.c_cc[VKILL]  = 0;
    t.c_cc[VMIN]   = 0;
    t.c_cc[VTIME]  = 1;
    if (set_term_param (&t) < 0)
                syslog(LOG_NOTICE,"Can't set terminal parameters:")
                ;
}
 
void break_sequence()
{
 
/*    tcsendbreak (0, 0);*/
}
 
/*void terminate(status)
int status;
{
    echo_stderr(-1);
 
    if (have_tty_parameters) {
        if (set_term_param (&saved_tty_parameters) < 0)
            fatal(2, "Can't restore terminal parameters: %m");
    }
}
*/
/*
 *      'Clean up' this string.
 */
char *clean(s, sending)
register char *s;
int sending;  /* set to 1 when sending (putting) this string. */
{
    char temp[STR_LEN], cur_chr;
    register char *s1, *phchar;
    int add_return = sending;
#define isoctal(chr) (((chr) >= '0') && ((chr) <= '7'))
 
    s1 = temp;
    while (*s) {
        cur_chr = *s++;
        if (cur_chr == '^') {
            cur_chr = *s++;
            if (cur_chr == '\0') {
                *s1++ = '^';
                break;
            }
            cur_chr &= 0x1F;
            if (cur_chr != 0) {
                *s1++ = cur_chr;
            }
            continue;
        }
 
        if (cur_chr != '\\') {
            *s1++ = cur_chr;
            continue;
        }
 
        cur_chr = *s++;
        if (cur_chr == '\0') {
            if (sending) {
                *s1++ = '\\';
                *s1++ = '\\';
            }
            break;
        }
 
        switch (cur_chr) {
        case 'b':
            *s1++ = '\b';
            break;
 
        case 'c':
            if (sending && *s == '\0')
                add_return = 0;
            else
                *s1++ = cur_chr;
            break;
 
        case '\\':
        case 'K':
        case 'p':
        case 'd':
            if (sending)
                *s1++ = '\\';
 
            *s1++ = cur_chr;
            break;
 
        case 'T':
            if (sending && phone_num) {
                for ( phchar = phone_num; *phchar != '\0'; phchar++)
                    *s1++ = *phchar;
            }
            else {
                *s1++ = '\\';
                *s1++ = 'T';
            }
            break;
 
        case 'U':
            if (sending && phone_num2) {
                for ( phchar = phone_num2; *phchar != '\0'; phchar++)
                    *s1++ = *phchar;
            }
            else {
                *s1++ = '\\';
                *s1++ = 'U';
            }
            break;
 
        case 'q':
            quiet = 1;
            break;
 
        case 'r':
            *s1++ = '\r';
            break;
 
        case 'n':
            *s1++ = '\n';
            break;
 
        case 's':
            *s1++ = ' ';
            break;
 
        case 't':
            *s1++ = '\t';
            break;
 
        case 'N':
            if (sending) {
                *s1++ = '\\';
                *s1++ = '\0';
            }
            else
                *s1++ = 'N';
            break;
 
        default:
            if (isoctal (cur_chr)) {
                cur_chr &= 0x07;
                if (isoctal (*s)) {
                    cur_chr <<= 3;
                    cur_chr |= *s++ - '0';
                    if (isoctal (*s)) {
                        cur_chr <<= 3;
                        cur_chr |= *s++ - '0';
                    }
                }
 
                if (cur_chr != 0 || sending) {
                    if (sending && (cur_chr == '\\' || cur_chr == 0))
                        *s1++ = '\\';
                    *s1++ = cur_chr;
                }
                break;
            }
 
            if (sending)
                *s1++ = '\\';
            *s1++ = cur_chr;
            break;
        }
    }
 
    if (add_return)
        *s1++ = '\r';
 
    *s1++ = '\0'; /* guarantee closure */
    *s1++ = '\0'; /* terminate the string */
    return dup_mem (temp, (size_t) (s1 - temp)); /* may have embedded nuls */
}
 
/*
 * A modified version of 'strtok'. This version skips \ sequences.
 */
 
char *expect_strtok (s, term)
     char *s, *term;
{
    static  char *str   = "";
    int     escape_flag = 0;
    char   *result;
 
/*
 * If a string was specified then do initial processing.
 */
    if (s)
        str = s;
 
/*
 * If this is the escape flag then reset it and ignore the character.
 */
    if (*str)
        result = str;
    else
        result = (char *) 0;
 
    while (*str) {
        if (escape_flag) {
            escape_flag = 0;
            ++str;
            continue;
        }
 
        if (*str == '\\') {
            ++str;
            escape_flag = 1;
            continue;
        }
 
/*
 * If this is not in the termination string, continue.
 */
        if (strchr (term, *str) == (char *) 0) {
            ++str;
            continue;
        }
 
/*
 * This is the terminator. Mark the end of the string and stop.
 */
        *str++ = '\0';
        break;
    }
    return (result);
}
 
/*
 * Process the expect string
 */
 
void   chat_expect (s)
char *s;
{
    char *expect;
    char *reply;
 
    if (strcmp(s, "HANGUP") == 0) {
        ++hup_next;
        return ;
    }
 
    if (strcmp(s, "ABORT") == 0) {
        ++abort_next;
        return ;
    }
 
    if (strcmp(s, "CLR_ABORT") == 0) {
        ++clear_abort_next;
        return ;
    }
 
    if (strcmp(s, "REPORT") == 0) {
        ++report_next;
        return ;
    }
 
    if (strcmp(s, "CLR_REPORT") == 0) {
        ++clear_report_next;
        return ;
    }
 
    if (strcmp(s, "TIMEOUT") == 0) {
        ++timeout_next;
        return ;
    }
 
    if (strcmp(s, "ECHO") == 0) {
        ++echo_next;
        return ;
    }
 
    if (strcmp(s, "SAY") == 0) {
        ++say_next;
        return ;
    }
 
/*
 * Fetch the expect and reply string.
 */
    for (;;) {
        expect = expect_strtok (s, "-");
        s      = (char *)0 ;
 
        if (expect == (char *) 0)
            return ;
 
        reply = expect_strtok (s, "-");
 
/*
 * Handle the expect string. If successful then exit.
 */
        if (get_string (expect))
            return;
 
/*
 * If there is a sub-reply string then send it. Otherwise any condition
 * is terminal.
 */
        if (reply == (char *) 0 || exit_code != 3)
            break;
 
        chat_send (reply);
    }
 
/*
 * The expectation did not occur. This is terminal.
 */
    return ;
}
 
/*
 *  process the reply string
 */
void chat_send (s)
register char *s;
{
    if (say_next) {
        say_next = 0;
        s = clean(s,0);
        write(modem_fd, s, strlen(s));
        free(s);
        return;
    }
 
    if (hup_next) {
        hup_next = 0;
    }
 
    if (echo_next) {
        echo_next = 0;
        echo = (strcmp(s, "ON") == 0);
        return;
    }
 
    if (abort_next) {
        /* char *s1; */
 
 
           ;
 
 
        return;
    }
 
 
/*    if (report_next) {
        char *s1;
 
        report_next = 0;
        if (n_reports >= MAX_REPORTS)
            {
              exit_code=2;
              return;
            }
 
        s1 = clean(s, 0);
 
        if (strlen(s1) > strlen(s) || strlen(s1) > sizeof fail_buffer - 1)
            {
              exit_code=1;
              return;
            }
 
        report_string[n_reports++] = s1;
 
        return;
    }
*/
/*    if (clear_report_next) {
        char *s1;
        int   i;
        int   old_max;
        int   pack = 0;
 
        clear_report_next = 0;
 
        s1 = clean(s, 0);
 
        if (strlen(s1) > strlen(s) || strlen(s1) > sizeof fail_buffer - 1)
            {
              exit_code=1;
              return;
            }
 
        old_max = n_reports;
        for (i=0; i < n_reports; i++) {
            if ( strcmp(s1,report_string[i]) == 0 ) {
                free(report_string[i]);
                report_string[i] = NULL;
                pack++;
                n_reports--;
            }
        }
        free(s1);
        if (pack)
            pack_array(report_string,old_max);
 
        return;
    }
*/
 
    if (timeout_next) {
        timeout=atoi(s);
        timeout_next = 0;
        chat_timeout = atoi(s);
 
        if (chat_timeout <= 0)
            chat_timeout = DEFAULT_CHAT_TIMEOUT;
 
 
        return;
    }
    if (strcmp(s, "EOT") == 0)
        s = "^D\\c";
    else if (strcmp(s, "BREAK") == 0)
        s = "\\K\\c";
 
    if (!put_string(s))
            {
              exit_code=1;
              return;
            }
}
 
int get_char()
{
    int status;
    char c;
    int tries=MAX_TIMEOUTS;
 
        while(tries)
        {
            status = read(modem_fd, &c, 1);
            switch (status) {
                   case 1:
                                return ((int)c & 0x7F);
                    default:
                                tries--;
            }
    }
        return -1;
}
 
int put_char(c)
int c;
{
    int status;
    char ch = c;
 
        /* inter-character typing delay (?) */
 
    status = write(modem_fd, &ch, 1);
 
    switch (status) {
    case 1:
        return (0);
 
    default:
 
 
    }
  return 0;
}
 
int write_char (c)
int c;
{
    if (put_char(c) < 0) {
        return (0);
    }
    return (1);
}
 
int put_string (s)
register char *s;
{
 
 
    quiet = 0;
    s = clean(s, 1);
    while (*s) {
        register char c = *s++;
 
        if (c != '\\') {
            if (!write_char (c))
                return 0;
            continue;
        }
 
        c = *s++;
        switch (c) {
        case 'd':
            sleep(1);
            break;
 
        case 'K':
            break_sequence();
            break;
 
        case 'p':
            usleep(10000);      /* 1/100th of a second (arg is microseconds) */
            break;
 
        default:
            if (!write_char (c))
                return 0;
            break;
        }
    }
 
   /* alarm(0);*/
    return (1);
}
 
/*
 *      Echo a character to stderr.
 *      When called with -1, a '\n' character is generated when
 *      the cursor is not at the beginning of a line.
 */
void echo_stderr(n)
int n;
{
/*    static int need_lf;
    char *s;
 
    switch (n) {
    case '\r':
        break;
    case -1:
        if (need_lf == 0)
            break;
 
    case '\n':
        write(2, "\n", 1);
        need_lf = 0;
        break;
    default:
        s = character(n);
        write(2, s, strlen(s));
        need_lf = 1;
        break;
    }*/
}
 
/*
 *      'Wait for' this string to appear on this file descriptor.
 */
 
int get_string(string)
register char *string;
{
    int c, len, minlen;
    register char *s = temp2, *end = s + STR_LEN;
    char *logged = temp2;
    struct termios tios;
 
    tcgetattr(modem_fd, &tios);
    tios.c_cc[VMIN] = 0;
    tios.c_cc[VTIME] = timeout*10/MAX_TIMEOUTS;
    tcsetattr(modem_fd, TCSANOW, &tios);
 
    string = clean(string, 0);
    len = strlen(string);
    minlen = (len > sizeof(fail_buffer)? len: sizeof(fail_buffer)) - 1;
 
    if (len > STR_LEN) {
        exit_code = 1;
        return 0;
    }
 
    if (len == 0) {
                        return (1);
    }
 
 
   while ( (c = get_char()) >= 0) {
                int n, abort_len;
 
        *s++ = c;
        *s=0;
 
        if (s - temp2 >= len &&
            c == string[len - 1] &&
            strncmp(s - len, string, len) == 0) {
            return (1);
        }
 
        for (n = 0; n < n_aborts; ++n) {
            if (s - temp2 >= (abort_len = strlen(abort_string[n])) &&
                strncmp(s - abort_len, abort_string[n], abort_len) == 0) {
 
                exit_code = n + 4;
                strcpy(fail_reason = fail_buffer, abort_string[n]);
                return (0);
            }
        }
 
        if (s >= end) {
            if (logged < s - minlen) {
                logged = s;
            }
            s -= minlen;
            memmove(temp2, s, minlen);
            logged = temp2 + (logged - s);
            s = temp2 + minlen;
        }
    }
    exit_code = 3;
    return (0);
}
 
/*
 * Gross kludge to handle Solaris versions >= 2.6 having usleep.
 */
 
/*
  usleep -- support routine for 4.2BSD system call emulations
  last edit:  29-Oct-1984     D A Gwyn
  */
 
 
#if 0
int
usleep( usec )                            /* returns 0 if ok, else -1 */
    long                usec;           /* delay in microseconds */
{
  rtems_status_code status;
  rtems_interval    ticks_per_second;
  rtems_interval    ticks;
  status = rtems_clock_get(
    RTEMS_CLOCK_GET_TICKS_PER_SECOND,
    &ticks_per_second);
    ticks = (usec * (ticks_per_second/1000))/1000;
    status = rtems_task_wake_after( ticks );
  return 0;
}
#endif
 
void pack_array (array, end)
    char **array; /* The address of the array of string pointers */
    int    end;   /* The index of the next free entry before CLR_ */
{
    int i, j;
 
    for (i = 0; i < end; i++) {
        if (array[i] == NULL) {
            for (j = i+1; j < end; ++j)
                if (array[j] != NULL)
                    array[i++] = array[j];
            for (; i < end; ++i)
                array[i] = NULL;
            break;
        }
    }
}
 
/*
 * vfmtmsg - format a message into a buffer.  Like vsprintf except we
 * also specify the length of the output buffer, and we handle the
 * %m (error message) format.
 * Doesn't do floating-point formats.
 * Returns the number of chars put into buf.
 */
#define OUTCHAR(c)      (buflen > 0? (--buflen, *buf++ = (c)): 0)
Browse

Tools

Subversion Repositories openrisc_2011-10-31

[/] [openrisc/] [trunk/] [rtos/] [rtems/] [c/] [src/] [libnetworking/] [pppd/] [chat.c] - Blame information for rev 173

Line No.	Rev	Author	Line
1	30	unneback	`/*`
2			`* Chat -- a program for automatic session establishment (i.e. dial`
3			`* the phone and log in).`
4			`*`
5			`* Standard termination codes:`
6			`* 0 - successful completion of the script`
7			`* 1 - invalid argument, expect string too large, etc.`
8			`* 2 - error on an I/O operation or fatal error condition.`
9			`* 3 - timeout waiting for a simple string.`
10			`* 4 - the first string declared as "ABORT"`
11			`* 5 - the second string declared as "ABORT"`
12			`* 6 - ... and so on for successive ABORT strings.`
13			`*`
14			`* This software is in the public domain.`
15			`*`
16			`* -----------------`
17			`* added -T and -U option and \T and \U substitution to pass a phone`
18			`* number into chat script. Two are needed for some ISDN TA applications.`
19			`* Keith Dart <kdart@cisco.com>`
20			`*`
21			`*`
22			`* Added SAY keyword to send output to stderr.`
23			`* This allows to turn ECHO OFF and to output specific, user selected,`
24			`* text to give progress messages. This best works when stderr`
25			`* exists (i.e.: pppd in nodetach mode).`
26			`*`
27			`* Added HANGUP directives to allow for us to be called`
28			`* back. When HANGUP is set to NO, chat will not hangup at HUP signal.`
29			`* We rely on timeouts in that case.`
30			`*`
31			`* Added CLR_ABORT to clear previously set ABORT string. This has been`
32			`* dictated by the HANGUP above as "NO CARRIER" (for example) must be`
33			`* an ABORT condition until we know the other host is going to close`
34			`* the connection for call back. As soon as we have completed the`
35			`* first stage of the call back sequence, "NO CARRIER" is a valid, non`
36			`* fatal string. As soon as we got called back (probably get "CONNECT"),`
37			`* we should re-arm the ABORT "NO CARRIER". Hence the CLR_ABORT command.`
38			`* Note that CLR_ABORT packs the abort_strings[] array so that we do not`
39			`* have unused entries not being reclaimed.`
40			`*`