You can use select (see perlfunc) to check whether data is available from a file descriptor.

Though, that could incur in a race condition, for instance, when the data is generated by another process running in parallel. So, you should probably set a safe waiting time (the last select argument).

In reply to Re: Using stdin only if there is input on it, but skipping it if there is no data by salva
in thread Using stdin only if there is input on it, but skipping it if there is no data by mldvx4

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