MINITALK - @42Wolfsburg

Purpose

Minitalk is in the second ring of the Core Curriculum @42Wolfsburg. 42 minitalk project is a collaboration between emomkus and qduong Our goal: 1. to practice git branching 2. collaborate together on project

Installation & Usage

Requirements

The only requirements are:

• GNU make (v3.81)
• GCC (12.0.0) (clang-1200.0.32.28)

Those versions are the ones used during development.

Building the program

1. Download/Clone this repo

    git clone https://github.com/qduong42/42_minitalk
   

2. cd into the 42_minitalk/srcs directory and run make

    cd 42_minitalk/srcs
    make
   

Running the program

After running make, execute ./server from the same folder. You should see Server pid: X Open another terminal in the same folder 42_minitalk/srcs and run ./client X [message-to-send]

Details about the project:

Communication method

Examination shows that we may use kill(USERSIG1, PID) kill(USERSIG2, PID) functions to signal the individual bits of characters of string. kill(USERSIG1, PID) may mean 0 and kill(USERSIG2, PID) may mean 1. Out of these bits server shall accumulate 8bit characters.

we use << shift operator, & bitwise AND and other bitwise operators to access individual bits

Using sigaction()

Technical Documentation of signal.h It explains that we shall define a struct sigaction to use function sigaction(). The technical documentation (https://pubs.opengroup.org/onlinepubs/009695399/basedefs/signal.h.html) defines function's sigaction() operation. Notice the argument data types:

	int sigaction(int sig, const struct sigaction *restrict act, struct sigaction *restrict oact);

	const struct sigaction

or

     struct sigaction

Using struct sigaction

It accepts struct sigaction in the same behabiour as any other datatype (int, char, char *). Contents of struct sigaction are predefined in signal.h library and are listed in technical documentation (https://man7.org/linux/man-pages/man2/sigaction.2.html).

			struct sigaction {
               void     (*sa_handler)(int);
               void     (*sa_sigaction)(int, siginfo_t *, void *);
               sigset_t   sa_mask;
               int        sa_flags;
               void     (*sa_restorer)(void);
        	};

1. void (*sa_handler)(int) - pointer to a signal handling function. This function receives the signal number as its only argument.
2. void (*sa_sigaction)(int, siginfo_t *, void *) -- dependant on architecture or flags, is used instead of sa_handler.
3. sigset_t sa_mask -- specifies a mask of signals which should be blocked.
4. sa_flags -- specifies a set of flags which modify the behavior of the signal like SA_SIGINFO.