sectionsize

Sectionsize is a term used to describe the length, typically measured in bytes, of a discrete portion of a larger structure such as a file, a memory region, or a document. It is usually recorded as a numeric field in header metadata and serves to locate, extract, validate, or load the data that belongs to that section.

In computing, sections are common in various contexts. In executable and object files, each section has a declared size that indicates how many bytes of payload belong to that section. A related concept is the in-memory or virtual size, which may differ from the on-disk size. In structured files or archives, sections correspond to blocks of data with a sectionsize that tells parsers how many bytes to read for that block.

In network protocols and data formats, sectionsized framing uses a length field to delimit a section within a message or stream, enabling sequential parsing and error detection. In document processing and publishing, sections can also be defined with an approximate size (words, characters, or pages) to guide layout, rendering, or quotas, though these are often higher-level abstractions than raw byte counts.

Calculation and validation are important for sectionsize: the declared size should match the actual payload length, and padding may be added to align sections to boundaries such as 4 or 8 bytes. Mismatches can indicate corruption, security risks, or parsing errors. Tools and viewers often expose sectionsize to help interpret file formats, debug loaders, and analyze memory layouts.

See also: section, offset, size, header, alignment.