Sample cURL application built using CLI tools

This article shows how to build sample application based on url2file cURL demo using command-line tools.

Prerequisites

It is assumed that you have already installed Samsung Customized Emscripten SDK as described in WebAssembly/Getting Started
You have installed either Tizen Studio or Tizen Studio with CLI(command line interface). See Quick-Start Gudie

Download url2file.c.
Note :
You can also clone whole repository from github.com.

Download CA certificates extracted from Mozilla:
```
curl -O https://curl.haxx.se/ca/cacert.pem
```

Compile url2file.c demo

emcc -o url2file.html -Os -s ENVIRONMENT_MAY_BE_TIZEN -s USE_CURL=1 --proxy-to-worker --preload-file cacert.pem url2file.c

Option	Description
`-Os`	Reduce size of generated WebAssembly module. This will reduce memory consumption of WebAssembly module compilation on Samsung Smart TV.
`-o url2file.html`	Name of the output, this will make that Emscripten will generate url2file.wasm, url2file.js and url2file.html
`-s ENVIRONMENT_MAY_BE_TIZEN`	Flag indicating that we want to use Samsung Tizen Emscripten extensions available on Samsung Smart TV. This flag is necessary to use POSIX sockets APIs in your application.
`-s USE_CURL=1`	Flage indicating that we want to build and use cURL library provided with Samsung Customized Emscripten. Note that during 1st build full library is being built, so compilation may take a while. However after 1st build cURL library is cached. See more on details on Emscripten Ports
`--proxy-to-worker`	This flag is needed to run `main()` function of your application in a Web Worker, because Samsung Tizen Sockets Extensions can only be used in a Web Worker.
`--preload-file cacert.pem`	This option allows your application to read cacert.pem file using standard C APIs `fopen(./cacert.pem)`

Implicitly enabled options:

Option	Description
`-s USE_SSL=1`	Flag enabling SSL library (libssl) from OpenSSL libraries. This flags is implicitly turned on by `-s USE_CURL=1`
`-s USE_CRYPTO=1`	Flag enabling use crypto library (libcrypto) from OpenSSL libraries. This flags is implicitly turned on by `-s USE_SSL=1`
`-s USE_ZLIB=1`	Flag enabling use of zlib compression library. This flag is implicitly turned on by `-s USE_CURL=1`

Further information regarding Emscripten build options can be found on Emscripten Compiler Frontend (emcc)

Download config.xml to the same directory where the demo was built.

Note:
- this application needs http://tizen.org/privilege/internet privilege
- content src attribute points to "url2file.html" instead of standard index.html, as this is what was generated by emcc.
More information regarding the config.xml file format can be found on Tizen Developers
Sign and pack widget using Tizen CLI interface:
```
tizen package -t wgt -s <YOUR_CERTIFICATE_PROFILE_NAME> -- .
```
Guide showing how to create certificate profile can be found at Creating Certificates

More information regarding Tizen CLI interface can be found at Command Line Interface Commands
Set your TV into developer mode as described in TV Device
Connect to the TV using sdb:
```
sdb connect <TV_IP>
```
SDB command and its options are described on Connecting Devices over Smart Development Bridge

List connected devices:

sdb devices

Sample output:

List of devices attached
192.168.13.2:26101      device          0