chat

automated modem and serial device conversation

TLDR

Execute a chat script directly

$ chat '[expect_send_pairs]'

Execute a chat script from a file

$ chat -f '[path/to/chat_script]'

Set a custom timeout

$ chat -t [timeout_in_seconds] '[expect_send_pairs]'

Enable verbose output to syslog

$ chat -v '[expect_send_pairs]'

Use a report file for logging

$ chat -r [path/to/report_file] '[expect_send_pairs]'

Dial a phone number using a variable

$ chat -T '[phone_number]' '"ATDT\\T CONNECT"'

Include an abort condition

$ chat 'ABORT "[error_string]" [expect_send_pairs]'

chat automates conversations with modems and serial devices by exchanging expect-send string pairs. It waits for an expected string from the device, then sends a response, repeating this process through a scripted sequence.The primary use case is establishing PPP (Point-to-Point Protocol) connections over serial lines and modems. A typical chat script initializes the modem with AT commands, dials a phone number, waits for a CONNECT response, and handles login sequences. Abort strings can be defined to terminate the script on error conditions like BUSY or NO CARRIER.chat is part of the ppp package and is typically invoked by pppd rather than run directly. Scripts can be specified inline on the command line or loaded from a file.