domsson / libkita

kita is a library to help you create, run and monitor child processes

libkita

This is a work in progress. Some things are not implemented. Other things might break.

libkita makes it easy to create and run child processes, monitor their activity, read their stdout and stderr output, as well as write to their stdin. It is not a one size fits all library; I'm writing this for a particular use-case and the library therefore makes certain assumptions and is lacking features that I don't need for my purposes.

Installation

First, build the library. There are two build scripts, for shared and static respectively. Let's go with shared:

chmod +x build-shared
./build-shared

The actual installation is dependent on your distribution, but usually means you'll have to copy the .h and the compiled .so to some system folder, then run a command to have the system re-load all libraries. For my Debian system, this does the trick:

cp ./lib/libkita.h /usr/include/
cp ./lib/libkita.so /usr/lib/x86_64-linux-gnu/
ldconfig -v -n /usr/lib

Alternatively, you could just put all source files into your project and compile them alongside your own code.

Usage

There will be more detailed documentation in the GitHub Wiki soon. Until then, see this simple example for an idea of how to use kita:

// Get a kita state struct
kita_state_s *kita = kita_init();

// Set callbacks, so we get informed of child events
kita_set_callback(kita, KITA_EVT_CHILD_READOK, on_child_readok);
kita_set_callback(kita, KITA_EVT_CHILD_CLOSED, on_child_closed);

// Get a kita child struct that will run the `date` command
char *cmd = "date +'%H:%M:%S'";
kita_child_s *child = kita_child_new(cmd, 0, 1, 0);

// Add the child to the kita state
kita_child_add(kita, child);

// Loop until some error or signal happens
kita_loop(kita);

A callback function could look like this:

void on_child_readok(kita_state_s *ks, kita_event_s *ke)
{
    // Read the data from the child
    char *output = kita_child_read(ke->child, ke->ios);

    // Print the data
    fprintf(stdout, "%s\n", output);

    // Free the data
    free(output);
}