Manual Pages  — ATOL

atol – convert ASCII string to long or long long integer

LIBRARY SYNOPSIS DESCRIPTION COMPATIBILITY ERRORS SEE ALSO STANDARDS

Standard C Library (libc, -lc)

#include <stdlib.h>

long
atol(const char *nptr);

long long
atoll(const char *nptr);

The atol() function converts the initial portion of the string pointed to by nptr to long integer representation.

It is equivalent to:

    strtol(nptr, (char **)NULL, 10);

The atoll() function converts the initial portion of the string pointed to by nptr to long long integer representation.

It is equivalent to:

    strtoll(nptr, (char **)NULL, 10);

The FreeBSD implementations of the atol() and atoll() functions are thin wrappers around strtol() and strtoll() respectively, so these functions will affect the value of errno in the same way that the strtol() and strtoll() functions are able to. This behavior of atol() and atoll() is not required by ISO/IEC 9899:1990 ("ISO C90") or ISO/IEC 9899:1999 ("ISO C99"), but it is allowed by all of ISO/IEC 9899:1990 ("ISO C90") and IEEE Std 1003.1-2001 ("POSIX.1").

The functions atol() and atoll() may affect the value of errno on an error.

The atol() function conforms to ISO/IEC 9899:1990 ("ISO C90"). The atoll() function conforms to ISO/IEC 9899:1999 ("ISO C99").