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

void backup(char * olddir, char * newdir)
{ int r = mkdir(newdir, 0700);
  if (r < 0)
  { perror("mkdir");
    exit(1); }
  DIR * old = opendir(olddir);
  struct dirent * de = readdir(old);
  while (de != NULL)
  { if (de->d_name[0] != '.')
    { printf("copy %s\n", de->d_name);
      if (de->d_type == DT_REG)
      { char from_name[1024], to_name[1024];
        sprintf(from_name, "%s/%s", olddir, de->d_name);
        sprintf(to_name, "%s/%s", newdir, de->d_name);
        printf("copying %s to %s\n", from_name, to_name);
        FILE * inf = fopen(from_name, "r");
        FILE * outf = fopen(to_name, "w");
        while (1)
        { int c = fgetc(inf);
          if (c == EOF) break;
          fputc(c, outf); }
        fclose(inf);
        fclose(outf); }
      else if (de->d_type == DT_DIR)
      { char fromdir[1024], todir[1024];
        sprintf(fromdir, "%s/%s", olddir, de->d_name);
        sprintf(todir, "%s/%s", newdir, de->d_name);
        printf("copying directory %s to %s\n", fromdir, todir);
        backup(fromdir, todir); } }       
    de = readdir(old); }
  closedir(old); }

int main(int argc, char * argv[])
{ if (argc != 3)
  { fprintf(stderr, "usage %s olddir newdir\n", argv[0]);
    exit(1); }
  char * olddir = argv[1], * newdir = argv[2];
  backup(olddir, newdir); }