$ gem update cocoapods
Updating installed gems
Nothing to update
$ pod --version
1.0.0
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$ gem install cocoapods
Successfully installed cocoapods-1.0.1
Parsing documentation for cocoapods-1.0.1
Done installing documentation for cocoapods after 3 seconds
1 gem installed
$ pod --version
1.0.0
How can I upgrade to 1.0.1?
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I think the problem is I installed two cocoapods via sudo gem install cocoapods and gem install cocoapods
So I remove all of them and install again, the version is correct now.