Reference

atoi(3)

convert ASCII string to integer

NAME

atoi, atoi_l – convert ASCII string to integer

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS

#include <stdlib.h>

int

atoi(const char *str);

#include <xlocale.h>

int

atoi_l(const char *str, locale_t loc);

DESCRIPTION

The atoi() function converts the initial portion of the string pointed to by str to int representation.

It is equivalent to:

(int)strtol(str, (char **)NULL, 10);

While the atoi() function uses the current locale, the atoi_l() function may be passed a locale directly. See xlocale(3) for more information.

IMPLEMENTATION NOTES

The atoi() and atoi_l() functions are thread-safe and async-cancel-safe.

The strtol() and strtol_l() functions are recommended instead of atoi() and atoi_l() functions, especially in new code.

ERRORS

The function atoi() need not affect the value of errno on an error.

SEE ALSO

atof(3), atol(3), strtod(3), strtol(3), strtoul(3), xlocale(3)

STANDARDS

The atoi() function conforms to ISO/IEC 9945-1:1990 (“POSIX.1”), ISO/IEC 9899:1990 (“ISO C90”), and ISO/IEC 9899:1999 (“ISO C99”).

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