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Command: atoi | Section: 3 | Source: OpenBSD | File: atoi.3
ATOI(3) FreeBSD Library Functions Manual ATOI(3)
NAME
atoi - convert ASCII string to integer
SYNOPSIS
#include <stdlib.h>
int
atoi(const char *nptr);
DESCRIPTION
The atoi() function converts the initial portion of the string pointed to
by nptr to integer representation.
It is equivalent to:
(int)strtol(nptr, (char **)NULL, 10);
SEE ALSO
atof(3), atol(3), strtod(3), strtol(3), strtonum(3), strtoul(3)
STANDARDS
The atoi() function conforms to ANSI X3.159-1989 ("ANSI C89").
HISTORY
An atoi() function first appeared in Version 1 AT&T UNIX.
CAVEATS
atoi does no overflow checking, handles unsigned numbers poorly, and
handles strings containing trailing extra characters (like "123abc")
poorly. Careful use of strtol(3) and strtoul(3) can alleviate these
problems, but strtonum(3) can be used to convert numbers from strings
much more safely and easily.
FreeBSD 14.1-RELEASE-p8 September 11, 2022 FreeBSD 14.1-RELEASE-p8