README.md

MFD - Modern FD

Small utility project for handling tasks, related to file descriptors (fds)

Functionality

Provides several types of FD structures:

• r_fd:
  • raw fd, contains fd (from kernel), writable and readable properties
• g_fd:
  • "general" fd, created from pipe2(), contains 2 r_fd (ro and wo)
• p_fd:
  • programmable fd, just buffer of bytes with used property

Provides neat functions for working with fds:

• mfd_write: Generic macro for all of 3 types fds to write bytes

• mfd_read: Generic macro for all of 3 types fds to read bytes

• mfd_redirect: reads from src fd and writes data to dest fd

• mfd_available: returns number of bytes, available for reading in fd

• mfd_set_flags: sets given flags for r_fd

• mfd_set_flags: returns flags of r_fd

Also provies streams, structure for dealing with fds easier. They can be used for convenient reading and writing:

• mfd_str_readexact: reads exactly N given bytes
• mfd_str_readmax: reads until no data available
• mfd_str_writeexact: writes exactly N given bytes

Example

#define _GNU_SOURCE
#include <mfd/streams.h>
#include <stdio.h>

int main(void){
	FILE *f = fopen("./assets/test.txt", "r");
	int fd = dup(fileno(f));
	fclose(f);

	mfd_stream str;

    // And readable and writeable
	mfd_str_create(fd, true, true, &str);

    // Reading all content of the file
	size_t size = 0;
	char   *content = NULL;
	mfd_str_readmax(str, &size, (void **)&content);

    // Closing stream
	mfd_str_end(&str);

	printf("Just read:\n%s\n", content);
	free(content);
}