Is it possible to call a JavaScript function (written over, say, node.js) from C?
(There are plenty of tutorials on calling C/C++ from node.js. But not the other way around.)
Asked
Active
Viewed 1,771 times
6
-
Er... I don't think there's a way, C programs can talk to the web. JavaScript is a language for the web. So, I feel, no. – Praveen Kumar Purushothaman Nov 06 '16 at 22:58
-
@Praveen: Node.js is used as a backend for non-web things all the time. – George Nov 06 '16 at 22:59
-
I know George, but generally, as a JavaScript... Well, I said it's just my feeling. – Praveen Kumar Purushothaman Nov 06 '16 at 23:00
-
C can use `system()` to execute shell commands, so you can do `system("npm scriptname.js")` – Barmar Nov 06 '16 at 23:01
-
@Barmar I think you mean `system("node scriptname.js")`? (npm is the package manager) – UnholySheep Nov 06 '16 at 23:02
-
@Barmer: I'm not interested in running the whole script, I'm interested in running a single function. – George Nov 06 '16 at 23:04
-
1@George Then put that function by itself in a script and execute that? – Andrew Li Nov 06 '16 at 23:04
-
@George I know you can embed a javascript interpreter (e.g.: SpiderMonkey) into a C program. But that would (potentially) be a lot of overhead. – UnholySheep Nov 06 '16 at 23:05
-
Yes, otherwise you need to use a JavaScript interpreter in your C environment. – Ram Nov 06 '16 at 23:05
-
Use SpiderMonkey? https://developer.mozilla.org/en-US/docs/Mozilla/Projects/SpiderMonkey/JSAPI_reference/JS_EvaluateScript – Bryan Chen Nov 06 '16 at 23:08
-
what's the function? is it pure javascript, or is that function calling out to other libraries? – Keith Nicholas Nov 07 '16 at 02:07
-
If you know what function to execute, may be pass it as a string argument to a node program, which eval()s it internally? – Tarun Gehlaut Jan 23 '17 at 15:29
-
You can use something like quickjs to do this. QuickJS (bellard) has a C api – Edwin Coronado Apr 05 '21 at 19:36
1 Answers
-1
You could use Emscripten.
Emscripten is an LLVM-to-JavaScript compiler.
It takes LLVM bitcode - which can be generated from C/C++, using llvm-gcc (DragonEgg) or clang, or any other language that can be converted into LLVM - and compiles that into JavaScript, which can be run on the web (or anywhere else JavaScript can run).
Also see this: How to execute Javascript function in C++
