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AGENTS.md

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+# Agent Instructions
+
+This repository contains the SDDS (Self Describing Data Sets) C/C++ library, utilities and related third‑party code.
+
+## Project Layout
+- `SDDSlib/` – Core implementation of the SDDS library written in C, providing routines for reading, writing and processing SDDS files.
+- `SDDSaps/` – Utility code for SDDS command‑line applications, including common processing and helper routines.
+- `include/` – Public header files for the SDDS library and other utilities.
+- `utils/` – Miscellaneous helper programs.
+- `fftpack/`, `lzma/`, `png/`, `tiff/`, `zlib/` – Third‑party libraries bundled with this project.
+- `matlib/`, `mdbcommon/`, `mdblib/`, `mdbmth/`, `meschach/`, `pgapack/`, `xlslib/`, etc. – Additional numerical and support libraries.
+- `rpm/`, `namelist/`, `2d_interpolate/`, `rpns/` – Specialized utilities and mathematical routines.
+
+Refer to `README.md` for build prerequisites and usage examples.
+
+## Coding Conventions
+After reviewing the source in `SDDSlib` and `SDDSaps`, the following conventions are used:
+- **Indentation:** Two spaces are used for each indentation level. Tabs are generally avoided.
+- **Braces:** Opening braces are placed on the same line as function or control statements.
+- **Comments:** Source files begin with Doxygen‑style block comments documenting the file, authorship, and licensing.
+- **Naming:** Functions use camelCase with a lowercase initial letter (e.g., `moveToStringArray`), while macros and constants are uppercase with underscores (e.g., `COLUMN_BASED`).
+- **Headers:** Standard C headers appear after project headers in `#include` lists.
+- **Line Length:** No strict maximum line length is enforced; some lines exceed 200 characters.
+
+These guidelines should be followed when contributing new code or documentation to maintain consistency with the existing project.