NAME

       strtol, strtoll - convert a string to a long integer

SYNOPSIS

       #include <stdlib.h>

       long strtol(const char *restrict str, char **restrict endptr, int base);
       long long strtoll(const char *restrict str, char **restrict endptr,
              int base)

DESCRIPTION

       These functions shall convert the initial portion of the string pointed to by str to a type long and long
       long representation, respectively. First, they decompose the input string into three parts:

        1. An initial, possibly empty, sequence of white-space characters (as specified by isspace())

        2. A  subject  sequence  interpreted  as an integer represented in some radix determined by the value of
           base

        3. A final string of one or more unrecognized characters, including the terminating  null  byte  of  the
           input string.

       Then they shall attempt to convert the subject sequence to an integer, and return the result.

       If the value of base is 0, the expected form of the subject sequence is that of a decimal constant, octal
       constant,  or hexadecimal constant, any of which may be preceded by a '+' or '-' sign. A decimal constant
       begins with a non-zero digit, and consists of a sequence of decimal digits. An octal constant consists of
       the prefix '0' optionally followed by a sequence of the digits '0' to '7' only.  A  hexadecimal  constant
       consists of the prefix 0x or 0X followed by a sequence of the decimal digits and letters 'a' (or 'A' ) to
       'f' (or 'F' ) with values 10 to 15 respectively.

       If  the  value  of  base  is between 2 and 36, the expected form of the subject sequence is a sequence of
       letters and digits representing an integer with the radix specified by base, optionally preceded by a '+'
       or '-' sign. The letters from 'a' (or 'A' ) to 'z' (or 'Z' ) inclusive are ascribed the values 10 to  35;
       only  letters whose ascribed values are less than that of base are permitted. If the value of base is 16,
       the characters 0x or 0X may optionally precede the sequence of letters and digits, following the sign  if
       present.

       The subject sequence is defined as the longest initial subsequence of the input string, starting with the
       first  non-white-space  character  that  is  of  the expected form. The subject sequence shall contain no
       characters if the input string is empty or consists entirely of white-space characters, or if  the  first
       non-white-space character is other than a sign or a permissible letter or digit.

       If  the  subject  sequence  has  the expected form and the value of base is 0, the sequence of characters
       starting with the first digit shall be interpreted as an integer constant. If the  subject  sequence  has
       the expected form and the value of base is between 2 and 36, it shall be used as the base for conversion,
       ascribing  to each letter its value as given above. If the subject sequence begins with a minus sign, the
       value resulting from the conversion shall be negated. A pointer to the final string shall  be  stored  in
       the object pointed to by endptr, provided that endptr is not a null pointer.

       In other than the C    or POSIX  locales, other implementation-defined subject sequences may be accepted.

       If  the  subject  sequence  is  empty or does not have the expected form, no conversion is performed; the
       value of str is stored in the object pointed to by endptr, provided that endptr is not a null pointer.

       The strtol() function shall not change the setting of errno if successful.

       Since 0, {LONG_MIN} or {LLONG_MIN}, and {LONG_MAX} or {LLONG_MAX} are returned  on  error  and  are  also
       valid  returns  on  success,  an application wishing to check for error situations should set errno to 0,
       then call strtol() or strtoll(), then check errno.

RETURN VALUE

       Upon successful completion, these functions shall return the converted value, if any.  If  no  conversion
       could be performed, 0 shall be returned    and errno may be set to [EINVAL].

       If  the  correct value is outside the range of representable values, {LONG_MIN}, {LONG_MAX}, {LLONG_MIN},
       or {LLONG_MAX} shall be returned (according to the sign of the value), and errno set to [ERANGE].

ERRORS

       These functions shall fail if:

       ERANGE The value to be returned is not representable.

       These functions may fail if:

       EINVAL The value of base is not supported.

       The following sections are informative.

EXAMPLES

       None.

APPLICATION USAGE

       None.

RATIONALE

       None.

FUTURE DIRECTIONS

       None.

SEE ALSO

       isalpha() , scanf() , strtod() , the Base Definitions volume of IEEE Std 1003.1-2001, <stdlib.h>

COPYRIGHT

       Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition,
       Standard for Information Technology -- Portable Operating System Interface (POSIX), The Open  Group  Base
       Specifications Issue 6, Copyright (C) 2001-2003 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 .

IEEE/The Open Group                                   2003                                             STRTOL(P)