advise me please, which is better or tell other ways 
$p = open P, 'xxx|'
1) while (sysread P) {...}; close P; wait();
2) while (1) {...if($p==waitpid($p,WNOHANG)){last}}; close P;

[download]
My os is Debian. Both works but which is more correct

In reply to how to determine pipe process terminated or alive by Anonymous Monk

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