I have a short function that takes a shell command, opens a pipe to it, and prints the output to both the screen and a log file (like tee). It works fine in most cases, but on occasion, I get the error "Modification of a read-only value attempted...".

Here's the code: 

open(PIPE, "$CommandToExecute|");
while (<PIPE>) { # <--- This is the line that the error points to
    print LOG $_; 
    print $_; 
}

[download]

I'm not sure what might be causing this error when I'm just reading a pipe. Like I said, this doesn't happen every time, just occasionally. What can I look for?

---
A fair fight is a sign of poor planning.

In reply to Modification of a read-only value by Sprad

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