Free Knowledge Resources


Linux Manual Pages


Free Software * Books

Source Code

Free Media

Linux

atoi(3)


NAME

   atoi, atol, atoll - convert a string to an integer

SYNOPSIS

   #include <stdlib.h>

   int atoi(const char *nptr);
   long atol(const char *nptr);
   long long atoll(const char *nptr);

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

   atoll():
       __ISOC99_SOURCE ||
           || /* Glibc versions <= 2.19: */ _BSD_SOURCE || _SVID_SOURCE

DESCRIPTION

   The  atoi() function converts the initial portion of the string pointed
   to by nptr to int.  The behavior is the same as

       strtol(nptr, NULL, 10);

   except that atoi() does not detect errors.

   The atol() and atoll() functions behave the same as atoi(), except that
   they  convert the initial portion of the string to their return type of
   long or long long.

RETURN VALUE

   The converted value.

ATTRIBUTES

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

   
   Interface                Attribute      Value          
   
   atoi(), atol(), atoll()  Thread safety  MT-Safe locale

CONFORMING TO

   POSIX.1-2001,  POSIX.1-2008,  C99,  SVr4, 4.3BSD.  C89 and POSIX.1-1996
   include the functions atoi() and atol() only.

NOTES

   Linux libc provided atoq() as an obsolete name for atoll();  atoq()  is
   not provided by glibc.

SEE ALSO

   atof(3), strtod(3), strtol(3), strtoul(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