Thanks ajorians!

I have already ported libmupdf, making a pdf viewer now.

http://whatdoestheinternetthink.net/compare/tsa-vs-nsa

Apparently TSA is more popular.

I am porting MuPDF, so PDF is not really necessary.

I don't see any zevio configs. And what are the names of the sp804 and clcd configs?

Yup, it's made with pdfTeX-1.40.14.

But I thought hardware revision I was OK.

@Roondak you can use nio_fgets and then use sscanf() (which is a syscall) to parse the string easily.

@ElementCoder the gets function doesn't receive the size of the buffer as a parameter; in standard C, it just writes until it sees a newline or EOF, which can lead to buffer overflows.
In NspireIO, nio_gets just calls nio_fgets with a size parameter of 100, so if you have a buffer of size at least 100, you're safe; otherwise, you must use nio_fgets.

EDIT: compu added nio_scanf and nio_sscanf