ATOI
Section: Linux Programmer's Manual (3)
Updated: 2016-03-15
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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 4.13 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/.
Index
- NAME
-
- SYNOPSIS
-
- DESCRIPTION
-
- RETURN VALUE
-
- ATTRIBUTES
-
- CONFORMING TO
-
- NOTES
-
- SEE ALSO
-
- COLOPHON
-