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

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

SYNOPSIS
       #include 

       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 featuretestmacros(7)):

       atoll():
           BSDSOURCE || SVIDSOURCE || XOPENSOURCE >= 600 ||
           ISOC99SOURCE || POSIXCSOURCE >= 200112L;
           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, 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.

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
       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 func‐
       tion in  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 3.53 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                               2012-08-03                           ATOI(3)