linux Fortran Question

[Padiyath Sreekumaran]

Hello,
Iam converting DEC fortran programs(Fortran 90) from Tru64 Unix to
Linux. 
Iam using pg(portland group) fortran90 on Linux. I have a problem
With the following Fortran statement:

Call system('ls -l out')

Error during compilation:
------------------------

PGF90-S-0084-Illegal use of symbol system - attempt to CALL a FUNCTION

Iam sorry when I ask this question here. How I have to convert this
statemnt
for pfg90?

Any help is very much appreciated. 
Iam very much thankful if I can have an example.

Thanks in advance.
Regards,
Kumar

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Padiyath Sreekumar       |   Tel: +41.56.310.3643
Paul Scherrer Institut   |   email: kumar.padiyath at psi.ch
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