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Using Putty, how can someone send a null character, ie \0

I have seen control+@ but that doesnt seem to work.

I'm trying to do manual SMTP AUTH:

AUTH PLAIN username\0\0password
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Use %x00 - this is known as UTF8NUL. – ott-- Mar 16 '13 at 16:45
Another possible issue: in the examples I've seen using AUTH PLAIN, it looks like the user name and password need to be Base64 encoded. – vjones Mar 16 '13 at 16:49
none of the methods from wikipedia or "alt+000" or "alt+256" seem to work for me. related:… – Ярослав Рахматуллин Mar 16 '13 at 22:17
control+@ is under Mac OSX only – portforwardpodcast Mar 17 '14 at 0:56
up vote 2 down vote accepted

The following worked for me when using PuTTY on windows with a local serial port.

  1. Under Window->Translation choose "ISO-8859-1:1998 (Latin-1, West Europe)"
  2. Send your null using alt+0256

On Mac I used the 'screen' program.

  1. Open the OS X terminal program, and run screen /dev/tty.SLAB_USBtoUART 115200 Use the path of your own serial device, something in /dev/tty.* 115200 was the baud for my specific device.
  2. Send null with ^@ (Ctrl+Shift+2). See This SU Post


  1. Serial Console on OSX
  2. SU Post
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