Special parameter $_ expands to a relative path

[Angel Tsankov]

Hello,

The Bash Reference Manual 
(http://www.gnu.org/s/bash/manual/bash.html#Special-Parameters) says:

At shell startup, [$_ is] set to the absolute pathname used to invoke 
the shell or shell script being executed as passed in the environment or 
argument list. [...]

However, with GNU bash, version 3.2.39 a simple script (named 'a'):

#!/bin/bash
echo "$_"

prints './a' when invoked as './a'.  According to the above excerpt, 
should it not print an absolute path to 'a' instead?


Regards,
Angel Tsankov