#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/types.h>
#include <dirent.h>
#include <errno.h>

#define BUFFER_MAX_SIZE 200
#define SIZE(x) ((x) > BUFFER_MAX_SIZE) ? BUFFER_MAX_SIZE : x

const char *MYLIB_PATH = "MYLIB_PATH=/home/richer";

/**
 * list files in directory identified by its name
 */
void find_files(char *dir_name) {
	DIR *dp;
	struct dirent *ep;

	dp = opendir (dir_name);
	if (dp != NULL) {
		while (ep = readdir (dp)) {
			if (!((strcmp(ep->d_name, ".") == 0) || 
				  (strcmp(ep->d_name, "..") == 0))) {
				printf("- %s\n", ep->d_name);
			}
		}
		(void) closedir (dp);
	} else {
		perror ("Couldn't open the directory");	
	}
}

/**
 * main function
 */
int main(int argc, char *argv[]) {
	char *path, *pbegin, *pend;
	char buffer[BUFFER_MAX_SIZE + 1];
	
	path = getenv("PATH");
	
	// get all paths and find files
	/*
	pbegin = path;
	pend = strchr(pbegin, ':');
	
	while (*pbegin != '\0') {
		if (pend == NULL) {
			strcpy(buffer, pbegin);
		} else {
			int size = pend-pbegin;
			strncpy(buffer, pbegin, SIZE(size));
			buffer[pend-pbegin] = '\0';	
		}	
		
		printf("===========================\n");
		printf("directory %s\n", buffer);
		printf("===========================\n");
		
		find_files(buffer);
		
		if (pend == NULL) break;
		
		pbegin = ++pend;
		pend = strchr(pbegin, ':');
		
	}	
	*/
	
	// or simplified version using strtok
	char *p = strtok(path, ":");
	while (p != NULL) {
		printf("===========================\n");
		printf("directory %s\n", p);
		printf("===========================\n");
		
		find_files(p);
		
		p = strtok(NULL, ":");
	}

	// play with setenv a
		
	if (!setenv("MYLIB_PATH", "/home/richer", 1) < 0) {
		fprintf(stderr, "could not set MYLIB_PATH with setenv !!!!\n");
	}
	
	if (putenv(const_cast<char *>(MYLIB_PATH))!=0) {
		fprintf(stderr, "could not set MYLIB_PATH with putenv => %d\n%s !!!!\n", 
		errno, strerror(errno));
	}
	
	system("echo $MYLIB_PATH");
	system("/home/richer/public_html/ens/inra/test_mylib.sh");
	
	return EXIT_SUCCESS;
}