pub fn read_file(path: &str) -> Result<String, &'static str>Expand description
A whole file, through the C library — std::fs::read_to_string for a
crate with no std. --params-file reads through it, and so do the
C / C++ surfaces’ own params-file entries.
The error is a short reason ("cannot be opened", "is not UTF-8", …),
for the caller to put beside the path it already holds.