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():
           _BSD_SOURCE || _SVID_SOURCE || _XOPEN_SOURCE >= 600 || _ISOC99_SOURCE ||
           _POSIX_C_SOURCE >= 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.

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

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