Keil Logo

About microlib

2.1 About microlib

Microlib is an alternative library to the default C library. It is intended for use with deeply embedded applications that must fit into extremely small memory footprints.

These applications do not run under an operating system.


Microlib does not attempt to be an ISO C-compliant library.
Microlib is highly optimized for small code size. It has less functionality than the default C library and some ISO C features are completely missing. Some library functions are also slower.
Functions in microlib are responsible for:
  • Creating an environment that a C program can execute in. This includes:
    • Creating a stack.
    • Creating a heap, if required.
    • Initializing the parts of the library the program uses.
  • Starting execution by calling main().
Non-ConfidentialPDF file icon PDF versionARM DUI0378H
Copyright © 2007, 2008, 2011, 2012, 2014-2016 ARM. All rights reserved. 
  Arm logo
Important information

This site uses cookies to store information on your computer. By continuing to use our site, you consent to our cookies.

Change Settings

Privacy Policy Update

Arm’s Privacy Policy has been updated. By continuing to use our site, you consent to Arm’s Privacy Policy. Please review our Privacy Policy to learn more about our collection, use and transfers
of your data.