SYSTEM
macro takes one argument: a command to execute. The command is
run via the standard C function system
. The presence of this macro in the
Yodl language introduces the danger of live data; imagine someone sending
you a document with
SYSTEM(rm *)
in it. To avoid such malevolent side effects, the yodl
program has a flag
-l
to define the `live data policy'. By default, -l0
is implied which
suppresses the SYSTEM
macro and the related PIPETHROUGH
macro. See also
section ??.
Despite the potential danger, SYSTEM
can be useful in many ways. E.g., you
might want to log when someone processes your document, as in:
SYSTEM(echo Document processed! | mail myself@my.host)
Please send Yodl questions and comments to yodl@icce.rug.nl.
Please send comments on these web pages to
(address unknown),
send other FSF & GNU inquiries and questions to
Copyright (c) 1998 Karel Kubat and Jan Nieuwenhuizen
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