SD partitions

Here is a SD card with one Fat32 partition and another one ext2 partition.
Windows 5.x machine reports only about the first Fat32 and of course does not recognize the ext2. Using an utility called dskwipe, we can see the list of partitions as Window sees them:

C:\>dskwipe.exe -l
one of the lines will be the SD device name (0 here - the whole device, 1 - the first partition):
\Device\Harddisk1\Partition0

To access to the ext2 partition from CoLinux running atop the Windows we need to do the following:

1. Add to the colinux.conf the following line
   cobd1="\Device\Harddisk1\Partition0"
2. Load CoLinux and run fdisk /dev/cobd1
3. Press 'u' to switch to block counting mode
4. Press 'p' to output the partitions
5. Write down the starting point of the ext2 partition multiplied by 512, say it will be 17754534912
6. Setup a loop device:
   losetup -o 17754534912 /dev/loop1 /dev/cobd1
7. Check the file system integrity:
   e2fsck /dev/loop1
   
8. Mount the partition:
   mount /dev/loop1 /media/sd_ext2

Windows utils

Some command line utilities I have learnt (again).

To test the originality of the system files:
sfc /scannow

To configure power setting if the powercfg.cpl UI can not be started:
powercfg.exe

Acer laptop brings troubles.

It can be called as a known fact, Windows on Acer's laptops stops working when the battery becomes weak. Nobody knows why, but the keyboard and the touchpad do not respond at all.
A solution for that - boot windows with removed battery and disable ACPI driver.

Also, acers have a hidden recovery partition, which should be accessible on Alt-F10 combination after the POST has done its job. But if the MBR record is overwritten, it's no longer there.
One can carefully restore the sector, it's template is located in a hidden partition's file (/ACER/TOOLS/RTMBR.bin). The file does not contains the partition table, so it should be taken from the existing MBR sector (back up it anyway).

Android dialog bug fixed

Cool, in Android SDK 2.0 the bug in which onPrepareDialog was not called on an activities reincarnation is fixed.

Improve internet connection

If windows internet connection slow or glitchy, try the following utility:
http://www.speedguide.net/files/TCPOptimizer.exe

To analyze the tcp/ip traffic, try Wireshark (http://www.wireshark.org/)

merge two files

To convenient merge two files use the diff utility with the -D option.
The command will be like:

diff -D _NEWFILE_ old_file.ext new_file.ext >result_file_to_edit.ext


With that -D option the result file will contain the C-preprocessor code, like

#ifdef _NEWFILE_
content only the new_file.ext
#endif /* _NEWFILE_ */

#ifndef _NEWFILE_
content only the old_file.ext
#endif /* _NEWFILE_ */

or

#ifndef _NEWFILE_
content only the old_file.ext
#else /* _NEWFILE_ */
content only the new_file.ext
#endif /* _NEWFILE_ */

Then use a text editor to manually search for the _NEWFILE_ string and modify the text
as you think it should be.

ftp thru a NAT firewall

I always was wondering, how ftp data connection gets through a firewall with NAT.
A ftp client on a machine with local IP (192.168.x.x) sends its own local address, like:
---> PORT 192,168,0,2,150,117
but the server still manages to establish the data connection to the client machine.
The answer to this question is simple - the NAT router works also on the application level and understands the ftp commands. When it sees the "PORT" command in the control connection, it translates the internal address to the external and adds a temporary record to the firewall table.

It's funny, but my simple cheap WiFi all-in-one box at home does the job when the ftp commands are upper cased and ignores it when it lowercased.

Good article about the subject here: