const char *zTail = z;
  while( z[0] ){
    if( z[0]=='/' ) zTail = &z[1];
    z++;
  }
  return zTail;
}

/*
** Return the head of a file pathname.  The head is everything leading up
** to the last component of the path.  For example, the head of "/a/b/c.d" is "/a/b".
** The trailing slash is removed.
*/
void file_head(const char *z, char *h){
  int i = file_tail(z)-z;
  if( !i ){
    memmove(h, z, strlen(z));
    return;
  }
  if( '/' == z[i-1] ) i--;
  memmove(h, z, i);
  h[i] = '\0';
}

/*
** Copy the content of a file from one place to another.
*/
void file_copy(const char *zFrom, const char *zTo){
  FILE *in, *out;
  int got;
  char zBuf[8192];
  in = fossil_fopen(zFrom, "rb");
  if( in==0 ) fossil_fatal("cannot open \"%s\" for reading", zFrom);
  file_head(zTo, zBuf);
  if( !file_isdir(zBuf) )
  {
    file_mkdir(zBuf, 0);
  }
  out = fossil_fopen(zTo, "wb");
  if( out==0 ) fossil_fatal("cannot open \"%s\" for writing", zTo);
  while( (got=fread(zBuf, 1, sizeof(zBuf), in))>0 ){
    fwrite(zBuf, 1, got, out);
  }
  fclose(in);
  fclose(out);