How do I securely get data transferred from C to Perl?

Suppose I have a perl program such as:

my $c = "MyDataToCProg";
open my $h, '-|', 'myCProg', "$c";
my @result = <$h>;
close $h;
print "Result: " . $result[0] . "\n";

Now, myCProg is a program compiled with gcc. The C program's output would be a printf statement which would end up in the perl program's $result[0] variable.

Is there a better way to extract output out of a C program than through printing with printf? For example, anyone could also run 'myCProg' from the command line and also see output. I want the output to only be seen in the perl program an NOT viewable if someone ran the program at the command line.

Anyone know how to do this?

Sorry, I don't have a C Program handy, but anything that has a printf statement (even a simple Hello World) and takes an argument (maybe prints "Hello [yourname]" would work for this example.

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Link to original article：https://stackoverflow.com/questions/32105815/how-do-i-securely-get-data-transferred-from-c-to-perl