Hi,
For using zgrep, you can install gzip package from AIX toolbox.
For installing gzip package, you can configure dnf in your system if it's not configured. https://www.ibm.com/support/pages/node/6585774
once dnf configuration is done, you can install gzip package like 'dnf install gzip'.
Thanks
Ranjit
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Ranjit Ranjan
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