readu and string instead of integer

[slayoo]

As reported by @GillesDuvert on SF.net:

READU, 'aaa', something

gives:

% Type conversion error: Unable to convert given STRING: 'aaa' to LONG.
... and GDL is waiting forever (waiting to read on unit 0 = the terminal)

OK, IDL has exactly the very same problem
but I believe GDL should throw an exception on this.

[slayoo]

With 0.9.8:

$ gdl -quiet
GDL> READU, 'aaa', something
% Type conversion error: Unable to convert given STRING: 'aaa' to LONG.

^C% Interrupt encountered.

^C% Interrupt encountered.

^C% Interrupt encountered.

Segmentation fault

[slayoo]

Further comments from SF.net:

@alaingdl on 2013-09-12:

for me, the exact issue is GDL crashes after, not IDL.

@alaingdl on 2013-09-28:

the problem of crash is related to lines 1886/1889 in basic_pro.cpp

1886 int pos = is->tellg();

this value is negative when playing with lun 0

and we also loose the contant when it is legitime to get it, e.g.:

str='abcd'
readu, 0, str

(we input for exemple: qwertyuiop and we should have 'qwer' inside str)