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formatting test

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Joseph Henry
2016-06-27 12:47:29 -07:00
parent 3c091125f9
commit 04213491cf
1 changed files with 31 additions and 11 deletions
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docs/linux_zt_sdk.md
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@@ -14,27 +14,47 @@ See [doc/docker_linux_zt_sdk.md](doc/docker_linux_zt_sdk.md)
## Short and sweet example
**Step 1: Make library and copy key files**
`make linux_shared_lib`
`mkdir /tmp/sdk-test-home`
`cp -f build/liblwip.so /tmp/sdk-test-home`
```
make linux_shared_lib
mkdir /tmp/sdk-test-home
cp -f build/liblwip.so /tmp/sdk-test-home
```
**Step 2: Start service and join network**
`./zerotier-sdk-service -d -p8000 /tmp/sdk-test-home`
`./zerotier-cli -D/tmp/sdk-test-home join 8056c2e21c000001`
**Step 3: Set environment variables**
`export LD_PRELOAD=`pwd`/build/libztintercept.so`
`export ZT_NC_NETWORK=/tmp/sdk-test-home/nc_8056c2e21c000001`
```
./zerotier-sdk-service -d -p8000 /tmp/sdk-test-home
./zerotier-cli -D/tmp/sdk-test-home join 8056c2e21c000001
```
**Step 4: Start application**
`node tests/httpserver.js`
**Step 3: Get new IP address assigned to app**
```
./zerotier-cli -D/tmp/sdk-test-home listnetworks
```
**Step 4: Set environment variables**
```
export LD_PRELOAD=`pwd`/build/libztintercept.so
export ZT_NC_NETWORK=/tmp/sdk-test-home/nc_8056c2e21c000001
```
**Step 5: Start application**
```
node tests/httpserver.js
```
**Step 6: Test it!**
From another system on the same virtual network `curl http://IP.ADD.RE.SS/`
*For a more in-depth explanation of what's happening here, see the section below:*
## Dynamic Linking
`make linux_shared_lib`
s
This will build a binary called `zerotier-sdk-service` and a library called `libztintercept.so`. It will also build the IP stack as `build/liblwip.so`.
The `zerotier-sdk-service` binary is almost the same as a regular ZeroTier One build except instead of creating virtual network ports using Linux's `/dev/net/tun` interface, it creates instances of a user-space TCP/IP stack for each virtual network and provides RPC access to this stack via a Unix domain socket. The latter is a library that can be loaded with the Linux `LD_PRELOAD` environment variable or by placement into `/etc/ld.so.preload` on a Linux system or container. Additional magic involving nameless Unix domain socket pairs and interprocess socket handoff is used to emulate TCP sockets with extremely low overhead and in a way that's compatible with select, poll, epoll, and other I/O event mechanisms.