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 4.15 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/.