pub fn load_header_by_field(
buf: &mut [u8],
offset: usize,
index: usize,
source: Source,
field: HeaderField,
) -> Result<usize, SysError>
Available on neither crate feature
native-simulator
nor crate feature stub-syscalls
.Expand description
Load header by field
Return the loaded data length or a syscall error
§Arguments
buf
- a writable buf used to receive the dataoffset
- offsetindex
- indexsource
- sourcefield
- field
§Example
let mut buf = [0u8; 8];
let len = load_header_by_field(&mut buf, 0, index, source, HeaderField::EpochNumber)?;
debug_assert_eq!(len, buf.len());