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STRTOL(3)                BSD Library Functions Manual                STRTOL(3)

     strtoimax, strtol, strtoll, strtoq -- convert a string value to a long,
     long long, intmax_t or quad_t integer

     Standard C Library (libc, -lc)

     #include <inttypes.h>

     strtoimax(const char *restrict str, char **restrict endptr, int base);

     #include <stdlib.h>

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

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

     #include <sys/types.h>
     #include <stdlib.h>
     #include <limits.h>

     strtoq(const char *str, char **endptr, int base);

     The strtol() function converts the string in str to a long value.  The
     strtoll() function converts the string in str to a long long value.  The
     strtoimax() function converts the string in str to an intmax_t value.
     The strtoq() function converts the string in str to a quad_t value.  The
     conversion is done according to the given base, which must be between 2
     and 36 inclusive, or be the special value 0.

     The string may begin with an arbitrary amount of white space (as deter-mined determined
     mined by isspace(3)) followed by a single optional `+' or `-' sign.  If
     base is zero or 16, the string may then include a ``0x'' prefix, and the
     number will be read in base 16; otherwise, a zero base is taken as 10
     (decimal) unless the next character is `0', in which case it is taken as
     8 (octal).

     The remainder of the string is converted to a long, long long, intmax_t
     or quad_t value in the obvious manner, stopping at the first character
     which is not a valid digit in the given base.  (In bases above 10, the
     letter `A' in either upper or lower case represents 10, `B' represents
     11, and so forth, with `Z' representing 35.)

     If endptr is not NULL, strtol() stores the address of the first invalid
     character in *endptr.  If there were no digits at all, however, strtol()
     stores the original value of str in *endptr.  (Thus, if *str is not `\0'
     but **endptr is `\0' on return, the entire string was valid.)

     Extended locale versions of these functions are documented in
     strtol_l(3).  See xlocale(3) for more information.

     The strtol(), strtoll(), strtoimax(), and strtoq() functions return the
     result of the conversion, unless the value would underflow or overflow.
     If no conversion could be performed, 0 is returned and the global vari-able variable
     able errno is set to EINVAL (the last feature is not portable across all
     platforms).  If an overflow or underflow occurs, errno is set to ERANGE
     and the function return value is clamped according to the following ta-ble. table.

           Function       underflow     overflow
           strtol()       LONG_MIN      LONG_MAX
           strtoll()      LLONG_MIN     LLONG_MAX
           strtoimax()    INTMAX_MIN    INTMAX_MAX
           strtoq()       LLONG_MIN     LLONG_MAX

     [EINVAL]           The value of base is not supported or no conversion
                        could be performed (the last feature is not portable
                        across all platforms).

     [ERANGE]           The given string was out of range; the value converted
                        has been clamped.

     #include <stdlib.h>
     #include <limits.h>

     <limits.h> is necessary for the strtol() and strtoll() functions.

     atof(3), atoi(3), atol(3), strtod(3), strtol_l(3), strtoul(3), wcstol(3),

     The strtol() function conforms to ISO/IEC 9899:1990 (``ISO C90'').  The
     strtoll() and strtoimax() functions conform to ISO/IEC 9899:1999
     (``ISO C99'').  The BSD strtoq() function is deprecated.

BSD                            November 28, 2001                           BSD