pub fn merge_env(block: &[u16], entries: &[EnvEntry]) -> Option<Vec<u16>>Expand description
Merge environment entries into a NAME=value\0...\0\0 block.
A name is matched case-insensitively; a value replaces in place or
appends, an entry without one removes. Drive entries (=C:=...) are left
alone. Returns None when nothing changed.