I learned that under LLVM, #including of <iostream> is forbidden.
Instead LLVM provides llvm::raw_ostream(for std::cout, std::cerr) and
llvm::MemoryBuffer(for input stream).
And using of llvm::raw_ostream is pretty easy but for me learning of
how to use llvm::MemoryBuffer is pretty much difficult.
I found a good sample code; utils/yaml2obj/yaml2obj.cpp.
The function, main() in this file provides a hint which is not enough
for me though.
I still cannot figure out how to use llvm::MemoryBuffer.
What I need is just a means of doing std::cin.
Could someone explain about this?
Thank you in advance.
Is this for user prompts, or just reading data from stdin? You can use MemoryBuffer::getSTDIN to read the contents of stdin into a memory buffer. Then you can get the data pointer and size and read it in. As far as I know, there is not a good way to implement user prompts with the LLVM APIs.
Hi Justin Holewinski,
As far as I know, there is not a good way to implement user prompts with the LLVM APIs.
This info helps me a lot.
I tried to do a thing that is not possible.
Thank you very much.
And for this kind of question I think I would better hold in.
There would be more important issue worth on this list.
For this reason I am sorry.
Hello Justin Holewinski,
I tested MemoryBuffer class.
And this test gives understanding of how to use it.
Though this is simple issue, I think I'd better post it here for
someone who might appear after me.
`~/Projects/build/Debug+Asserts/bin/llvm-config --cppflags --ldflags
--libs core` -o memorybuffertest
./memorybuffertest <any .txt file input>
--> tests input of a file
--> tests input of STDIN
MemoryBufferTest.cpp follows below.
using namespace llvm;
int main(int argc, char **argv)
if (argc != 2) return 1;
if (MemoryBuffer::getFileOrSTDIN(argv, Buf))
llvm::errs() << "size : " << Buf->getBufferSize() << "\n";
llvm::errs() << "start : " << Buf->getBufferStart() << "\n";
llvm::errs() << "end : " << Buf->getBufferEnd() << "\n";
llvm::errs() << "buffer : " << Buf->getBuffer() << "\n";