C Standard Library About the Tutorial C is a general-purpose, procedural, imperative computer programming language developed in 1972 by Dennis M. Ritchie at the Bell Telephone Laboratories to develop the Unix operating system. C is the most widely used computer language that keeps fluctuating at number one scale of popularity along with Java programming language which is also equally popular and most widely used among modern software programmers. The C Standard Library is a set of C built-in functions, constants and header files like <assert.h>, <ctype.h>, etc. This library will work as a reference manual for C programmers. Audience The C Standard Library is a reference for C programmers to help them in their projects related to system programming. All the C functions have been explained in a user- friendly way and they can be copied and pasted in your C projects. Prerequisites A basic understanding of the C Programming language will help you in understanding the C built-in functions covered in this library. Copyright & Disclaimer Copyright 2014 by Tutorials Point (I) Pvt. Ltd. All the content and graphics published in this e-book are the property of Tutorials Point (I) Pvt. Ltd. The user of this e-book is prohibited to reuse, retain, copy, distribute or republish any contents or a part of contents of this e-book in any manner without written consent of the publisher. We strive to update the contents of our website and tutorials as timely and as precisely as possible, however, the contents may contain inaccuracies or errors. Tutorials Point (I) Pvt. Ltd. provides no guarantee regarding the accuracy, timeliness or completeness of our website or its contents including this tutorial. If you discover any errors on our website or in this tutorial, please notify us at [email protected] i C Standard Library Table of Contents About the Tutorial .................................................................................................................................... i Audience .................................................................................................................................................. i Prerequisites ............................................................................................................................................ i Copyright & Disclaimer ............................................................................................................................. i Table of Contents .................................................................................................................................... ii 1. C LIBRARY ─ <ASSERT.H> ..................................................................................................... 1 Introduction ............................................................................................................................................ 1 Library Macros ........................................................................................................................................ 1 2. C LIBRARY ─ <CTYPE.H> ....................................................................................................... 3 Introduction ............................................................................................................................................ 3 Library Functions ..................................................................................................................................... 3 Character Classes .................................................................................................................................. 24 3. C LIBRARY ─ <ERRNO.H> .................................................................................................... 26 Introduction .......................................................................................................................................... 26 Library Macros ...................................................................................................................................... 26 4. C LIBRARY ─ <FLOAT.H> ..................................................................................................... 31 Introduction .......................................................................................................................................... 31 Library Macros ...................................................................................................................................... 31 5. C LIBRARY ─ <LIMITS.H> .................................................................................................... 34 Introduction .......................................................................................................................................... 34 Library Macros ...................................................................................................................................... 34 6. C LIBRARY ─ <LOCALE.H> ................................................................................................... 37 Introduction .......................................................................................................................................... 37 Library Macros ...................................................................................................................................... 37 ii C Standard Library Library Functions ................................................................................................................................... 38 Library Structure ................................................................................................................................... 42 7. C LIBRARY ─ <MATH.H> ..................................................................................................... 45 Introduction .......................................................................................................................................... 45 Library Macros ...................................................................................................................................... 45 Library Functions ................................................................................................................................... 45 8. C LIBRARY ─ <SETJMP.H> ................................................................................................... 68 Introduction .......................................................................................................................................... 68 Library Variables ................................................................................................................................... 68 Library Macros ...................................................................................................................................... 68 Library Functions ................................................................................................................................... 70 9. C LIBRARY ─ <SIGNAL.H> ................................................................................................... 72 Introduction .......................................................................................................................................... 72 Library Variables ................................................................................................................................... 72 Library Macros ...................................................................................................................................... 72 Library Functions ................................................................................................................................... 73 10. C LIBRARY ─ <STDARG.H> .................................................................................................. 78 Introduction .......................................................................................................................................... 78 Library Variables ................................................................................................................................... 78 Library Macros ...................................................................................................................................... 78 11. C LIBRARY ─ <STDDEF.H> ................................................................................................... 83 Introduction .......................................................................................................................................... 83 Library Variables ................................................................................................................................... 83 Library Macros ...................................................................................................................................... 83 iii C Standard Library 12. C LIBRARY ─ <STDIO.H> ..................................................................................................... 87 Introduction .......................................................................................................................................... 87 Library Variables ................................................................................................................................... 87 Library Macros .....................................................................................................................................