ATOI(3)                                             Linux Programmer's Manual                                            ATOI(3)



NAME
       atoi, atol, atoll, atoq - 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);
       long long atoq(const char *nptr);

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

       atoll(): _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE; or cc -std=c99

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, (char **) 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.  atoq() is an obsolete name for atoll().

RETURN VALUE
       The converted value.

CONFORMING TO
       SVr4, POSIX.1-2001, 4.3BSD, C99.  C89 and POSIX.1-1996 include the functions atoi() and atol() only.   atoq()  is  a  GNU
       extension.

NOTES
       The  nonstandard  atoq()  function is not present in libc 4.6.27 or glibc 2, but is present in libc5 and libc 4.7 (though
       only as an inline function in <stdlib.h> until libc 5.4.44).  The atoll() function is present in glibc  2  since  version
       2.0.2, but not in libc4 or libc5.

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

COLOPHON
       This  page  is  part of release 3.25 of the Linux man-pages project.  A description of the project, and information about
       reporting bugs, can be found at http://www.kernel.org/doc/man-pages/.



GNU                                                        2007-07-26                                                    ATOI(3)