Free Knowledge Resources


Linux Manual Pages


Free Software * Books

Source Code

Free Media

Linux

labs(3)


NAME

   abs, labs, llabs, imaxabs - compute the absolute value of an integer

SYNOPSIS

   #include <stdlib.h>

   int abs(int j);
   long int labs(long int j);
   long long int llabs(long long int j);

   #include <inttypes.h>

   intmax_t imaxabs(intmax_t j);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

   llabs():
       _ISOC99_SOURCE || _POSIX_C_SOURCE >= 200112L

DESCRIPTION

   The  abs() function computes the absolute value of the integer argument
   j.  The labs(), llabs() and imaxabs() functions  compute  the  absolute
   value  of  the  argument  j  of  the  appropriate  integer type for the
   function.

RETURN VALUE

   Returns the absolute value of the integer argument, of the  appropriate
   integer type for the function.

ATTRIBUTES

   For   an   explanation   of   the  terms  used  in  this  section,  see
   attributes(7).

   ┌───────────────────┬───────────────┬─────────┐
   │Interface          │ Attribute     │ Value   │
   ├───────────────────┼───────────────┼─────────┤
   │abs(), labs(),     │ Thread safety │ MT-Safe │
   │llabs(), imaxabs() │               │         │
   └───────────────────┴───────────────┴─────────┘

CONFORMING TO

   POSIX.1-2001,  POSIX.1-2008,  C99, SVr4, 4.3BSD.  C89 only includes the
   abs() and labs() functions; the functions llabs()  and  imaxabs()  were
   added in C99.

NOTES

   Trying  to  take the absolute value of the most negative integer is not
   defined.

   The llabs() function is included  in  glibc  since  version  2.0.   The
   imaxabs() function is included in glibc since version 2.1.1.

   For   llabs()   to   be   declared,  it  may  be  necessary  to  define
   _ISOC99_SOURCE or _ISOC9X_SOURCE (depending on the  version  of  glibc)
   before including any standard headers.

   By  default, GCC handles abs(), labs(), and (since GCC 3.0) llabs() and
   imaxabs() as built-in functions.

SEE ALSO

   cabs(3), ceil(3), fabs(3), floor(3), rint(3)

COLOPHON

   This page is part of release 4.09 of the Linux  man-pages  project.   A
   description  of  the project, information about reporting bugs, and the
   latest    version    of    this    page,    can     be     found     at
   https://www.kernel.org/doc/man-pages/.



Opportunity


Personal Opportunity - Free software gives you access to billions of dollars of software at no cost. Use this software for your business, personal use or to develop a profitable skill. Access to source code provides access to a level of capabilities/information that companies protect though copyrights. Open source is a core component of the Internet and it is available to you. Leverage the billions of dollars in resources and capabilities to build a career, establish a business or change the world. The potential is endless for those who understand the opportunity.

Business Opportunity - Goldman Sachs, IBM and countless large corporations are leveraging open source to reduce costs, develop products and increase their bottom lines. Learn what these companies know about open source and how open source can give you the advantage.



Free Software


Free Software provides computer programs and capabilities at no cost but more importantly, it provides the freedom to run, edit, contribute to, and share the software. The importance of free software is a matter of access, not price. Software at no cost is a benefit but ownership rights to the software and source code is far more significant.

Free Office Software - The Libre Office suite provides top desktop productivity tools for free. This includes, a word processor, spreadsheet, presentation engine, drawing and flowcharting, database and math applications. Libre Office is available for Linux or Windows.



Free Books


The Free Books Library is a collection of thousands of the most popular public domain books in an online readable format. The collection includes great classical literature and more recent works where the U.S. copyright has expired. These books are yours to read and use without restrictions.

Source Code - Want to change a program or know how it works? Open Source provides the source code for its programs so that anyone can use, modify or learn how to write those programs themselves. Visit the GNU source code repositories to download the source.



Education


Study at Harvard, Stanford or MIT - Open edX provides free online courses from Harvard, MIT, Columbia, UC Berkeley and other top Universities. Hundreds of courses for almost all major subjects and course levels. Open edx also offers some paid courses and selected certifications.

Linux Manual Pages - A man or manual page is a form of software documentation found on Linux/Unix operating systems. Topics covered include computer programs (including library and system calls), formal standards and conventions, and even abstract concepts.


birds banner