On 27 мар, 03:50, [EMAIL PROTECTED] (Ultra Star X) wrote:
> I am really going crazy here. I have the following system call that I
> would like to run from perl:
> "ls *.txt | xargs cat > out"
> if *.txt does not exist then I expect to get an exit code different
> from 0.
>
> So to test I do:
>
> use strict;
>
> my $f = "file_which_does_not_exist";
>
> # method 1
> print "test 1\n";
> qx(ls $f | xargs cat);
> print $?,"\n";
>
> #method 2
> print "test 2\n";
> system("ls $f | xargs cat");
> print $?,"\n";
>
> Both calls return 0 instead of returning error as 'ls' fails.
> Help. How do I do this ?
> Would 'open' help ?
So Jeff already explained why. Now what can be done.
One way: if you still want to run this command line correctly, try
IPC::Run. It is a bit tricky to use first, but can safely run any
pipelines.
Another way: try using native Perl methods. opendir() and readdir()
instead of ls, match file names with regex, and then read and append
files, or run cat.
/sandy
http://myperlquiz.com/
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