This is not sed(1) overwriting the output file, it is the shell. Redirection  > pbxiplp1 is a shell operation - if the file already exists it clobbers it (truncates to zero bytes). This is done by the shell before the sed(1) program is executed. By the time poor old sed gets to read the file the data is long gone.

Use perl for this, or redirect to a different filename then rename it.
Misread the question.

In reply to Re: sed deleting file by cdarke
in thread sed deleting file by ddrew78

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