Fix unable to create a new stream error on android system.

[dongfengweixiao]

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• Version of iperf3 (or development branch, such as master or
  3.1-STABLE) to which this pull request applies:

master

• Issues fixed (if any):

none

• Brief description of code changes (suitable for use as a commit message):

when run iperf3 on android as server,

/data/local/tmp/iperf3 -s                                          
-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------
Accepted connection from 192.168.0.2, port 61642
iperf3: error - unable to create a new stream: No such file or directory
-----------------------------------------------------------
Server listening on 5201
-----------------------------------------------------------

cause iperf3 use ‘/tmp’ as default tmp folder, but android only support ‘/data/local/tmp’.

[davidBar-On]

@bmah888, I believe that this is a desired change for Android users and that there is no risk from the changes for non-Android users.

Note that there is a iperf3 repository for Android that was maintained up to iperf3 version 3.10.1 (I don't know more than that), and it seems that the only change to the source code was the change suggested by this PR - see this script.

[bmah888]

@bmah888, I believe that this is a desired change for Android users and that there is no risk from the changes for non-Android users.

Note that there is a iperf3 repository for Android that was maintained up to iperf3 version 3.10.1 (I don't know more than that), and it seems that the only change to the source code was the change suggested by this PR - see this script.

Tentatively I agree, this is probably low-risk change and helpful.

[swlars]

Thanks for the pull request!