```{index} single: remap; File::Map function ``` ```{index} single: File::Map::remap; Perl function ``` # remap Resize an existing mapping in place. ## Synopsis ```perl remap $map, $new_size; ``` ## Arguments - `$lvalue` — a currently mapped scalar. - `$new_size` — new length in bytes. Must be greater than zero. ## When it applies `remap` is Linux-specific. It wraps `mremap(2)` with `MREMAP_MAYMOVE`, so the scalar may end up pointing to a different virtual address after the call. - For a file-backed mapping, the underlying file must be large enough to cover `$new_size`, or accessing the extra pages will produce a bus fault. - Anonymous shared mappings cannot be remapped. Use with caution on production data. ## Differences from upstream Fully compatible with upstream `File::Map` 0.71. ## See also - `map_file` — pick the right size up front if you can. - `unmap` — drop the mapping entirely instead of resizing.