atol(3p) — Linux manual page

ATOL(3P)                POSIX Programmer's Manual                ATOL(3P)

PROLOG         top

       This manual page is part of the POSIX Programmer's Manual.  The
       Linux implementation of this interface may differ (consult the
       corresponding Linux manual page for details of Linux behavior), or
       the interface may not be implemented on Linux.

NAME         top

       atol, atoll — convert a string to a long integer

SYNOPSIS         top

       #include <stdlib.h>

       long atol(const char *nptr);
       long long atoll(const char *nptr);

DESCRIPTION         top

       The functionality described on this reference page is aligned with
       the ISO C standard. Any conflict between the requirements
       described here and the ISO C standard is unintentional. This
       volume of POSIX.1‐2017 defers to the ISO C standard.

       Except as noted below, the call atol(nptr) shall be equivalent to:

           strtol(nptr, (char **)NULL, 10)

       Except as noted below, the call to atoll(nptr) shall be equivalent
       to:

           strtoll(nptr, (char **)NULL, 10)

       The handling of errors may differ. If the value cannot be
       represented, the behavior is undefined.

RETURN VALUE         top

       These functions shall return the converted value if the value can
       be represented.

ERRORS         top

       No errors are defined.

       The following sections are informative.

EXAMPLES         top

       None.

APPLICATION USAGE         top

       If the number is not known to be in range, strtol() or strtoll()
       should be used because atol() and atoll() are not required to
       perform any error checking.

RATIONALE         top

       None.

FUTURE DIRECTIONS         top

       None.

SEE ALSO         top

       strtol(3p)

       The Base Definitions volume of POSIX.1‐2017, stdlib.h(0p)

COPYRIGHT         top

       Portions of this text are reprinted and reproduced in electronic
       form from IEEE Std 1003.1-2017, Standard for Information
       Technology -- Portable Operating System Interface (POSIX), The
       Open Group Base Specifications Issue 7, 2018 Edition, Copyright
       (C) 2018 by the Institute of Electrical and Electronics Engineers,
       Inc and The Open Group.  In the event of any discrepancy between
       this version and the original IEEE and The Open Group Standard,
       the original IEEE and The Open Group Standard is the referee
       document. The original Standard can be obtained online at
       http://www.opengroup.org/unix/online.html .

       Any typographical or formatting errors that appear in this page
       are most likely to have been introduced during the conversion of
       the source files to man page format. To report such errors, see
       https://www.kernel.org/doc/man-pages/reporting_bugs.html .

IEEE/The Open Group                2017                          ATOL(3P)

Pages that refer to this page: stdlib.h(0p)

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