Thread: transfer binary over socket

Looking at this in the fresh morning air, I realized what a mess I had made (no thanks to master5001, but much to RobSeace...)

So for posterity, here's my working code for binary transfer on a local unix socket (for which there may be a few uses, who knows?):

Code:

#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <sys/stat.h>

	
int loclconn (char *socket, int fd) { 
	size_t size;
	struct sockaddr_un peer;
	peer.sun_family=AF_LOCAL;
	strcpy(peer.sun_path,socket);
	size=SUN_LEN(&peer);
	return connect(fd,(struct sockaddr*)&peer,size);
} 


int loclsckt (char *file) {
	struct sockaddr_un name;
	int sock;
	size_t size;

	if ((strlen(file)) > 107) return -2;
	if ((sock=socket(PF_LOCAL,SOCK_STREAM,0)) < 0) return -1;
	
	name.sun_family = AF_LOCAL;	
	strcpy(name.sun_path, file);
	size=SUN_LEN(&name);
	if ((bind(sock,(struct sockaddr*)&name,size) < 0)) return -3;
	return sock;
}


int main (int argc, char *argv[]) {
	int pid, CHLD, PRNT, IN;
	size_t len;
	int bytes;
	char *buffer, *buffer2;
	struct stat finfo;
	FILE *fstRO = fopen(argv[1], "rb");
	FILE *fstW = fopen("/root/test/image.jpg", "wb");
	struct sockaddr addr;

	if (fstRO == NULL) {
		puts("valid filename required");
		return -1;}
	
	stat(argv[1],&finfo);
	bytes=finfo.st_size;
	buffer=malloc(bytes);
	buffer2=malloc(bytes);
	
	fread(buffer,bytes,1,fstRO);
	fclose(fstRO);
	
	PRNT=loclsckt("/root/test/testsock");
	listen(PRNT,5);
	if ((CHLD=socket(PF_LOCAL,SOCK_STREAM,0)) < 0) perror("socket");

	pid=fork();
	if (pid == 0) {
		if (loclconn("/root/test/testsock",CHLD) < 0) perror("localconn");
		if(write(CHLD,buffer,bytes) == -1) perror("write");
		close(CHLD);
		return;
	} 
	IN=accept(PRNT,&addr,&len);
	read(IN,buffer2,bytes);
	close(IN);
	close(PRNT);
	unlink("/root/test/testsock");

	fwrite(buffer2,bytes,1,fstW);
	fclose(fstW);
}