minitalk

client <-> server communication via signal SIGUSR1, SIGUSR2

Features

• the ACK timeout, connection lost timeout is customizable
• the server can receive any character, even include null ('\0')
• the server is not strongly affected by malicious clients

Prerequisite

• POSIX-compliant OS
• GNU Make

Build

make -C src

to see executed commands, set environment variable V=1

make -C src V=1

Usage

there's two executables, server and client

server

the server will print the server's PID, and wait for the client

client

pass the server's PID as the first argument

pass the message as the second argument

./client "${PID_OF_SERVER}" "${MESSAGE_TO_SEND}"

Options

all options passed to the environment variable:

Server options

• TIMEOUT: ACK timeout in microseconds
• BUFFER_SIZE: ACK timeout in microseconds
• MESSAGE_FORMAT_HEADER: message template for header
• MESSAGE_FORMAT_LINE: message template for each line
• MESSAGE_FORMAT_FOOTER: message template for footer
• MESSAGE_FORMAT_TIMEOUT: message template for footer

MESSAGE_FORMAT_HEADER, MESSAGE_FORMAT_FOOTER, MESSAGE_FORMAT_TIMEOUT is printf-like format string

• %%: literal character %
• %P: client's PID
• %L: message's length
• %_: space
• %T: tab
• %L: line break

for MESSAGE_FORMAT_LINE, only %T is supported. no way to express %T

Client options

Example

server

user@m1jy src % ./server
Server pid is 18889. enjoy!
Message from 18895 (12 bytes)
|       Hello world!

Message from 18915 (102 bytes)
|
|       #ifndef FT_EXIT_H
|       # define FT_EXIT_H
|
|       # include <stdlib.h>
|
|       int             ft_exit(signed char status);
|
|       #endif

client

user@m1jy src % ./client 18889 'Hello world!'
user@m1jy src % ./client 18889 \
>               "$(cat ft_exit.h | grep -v '*')"
user@m1jy src %

Future plans

• separate client library
• enhance message formatter
• ... issues welcomed!