Fossil

  };
  static const unsigned char zChars[] =
    "abcdefghijklmnopqrstuvwxyz"
    "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
    "0123456789";
  unsigned int i, j;
  const char *zDir = ".";
  int cnt = 0;
  
  for(i=0; i<sizeof(azDirs)/sizeof(azDirs[0]); i++){
    if( !file_isdir(azDirs[i]) ) continue;
    zDir = azDirs[i];
    break;
  }

  /* Check that the output buffer is large enough for the temporary file 
  ** name. If it is not, return SQLITE_ERROR.
  */
  if( (strlen(zDir) + 17) >= (size_t)nBuf ){
    fossil_fatal("insufficient space for temporary filename");
  }

  do{
    if( cnt++>20 ) fossil_panic("cannot generate a temporary filename");
    sqlite3_snprintf(nBuf-17, zBuf, "%s/", zDir);
    j = (int)strlen(zBuf);
    sqlite3_randomness(15, &zBuf[j]);
    for(i=0; i<15; i++, j++){
      zBuf[j] = (char)zChars[ ((unsigned char)zBuf[j])%(sizeof(zChars)-1) ];
    }
    zBuf[j] = 0;
  }while( file_size(zBuf)>=0 );
}


/*
** Return true if a file named zName exists and has identical content
** to the blob pContent.  If zName does not exist or if the content is
** different in any way, then return false.