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STRTOL(3)             DragonFly Library Functions Manual             STRTOL(3)

NAME

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

LIBRARY

Standard C Library (libc, -lc)

SYNOPSIS

#include <stdlib.h> #include <limits.h> long strtol(const char * restrict nptr, char ** restrict endptr, int base); long long strtoll(const char * restrict nptr, char ** restrict endptr, int base); #include <inttypes.h> intmax_t strtoimax(const char * restrict nptr, char ** restrict endptr, int base); #include <sys/types.h> quad_t strtoq(const char *nptr, char **endptr, int base); #include <xlocale.h> long strtol_l(const char * restrict nptr, char ** restrict endptr, int base, locale_t locale); long long strtoll_l(const char * restrict nptr, char ** restrict endptr, int base, locale_t locale); intmax_t strtoimax_l(const char * restrict nptr, char ** restrict endptr, int base, locale_t locale);

DESCRIPTION

The strtol() and strtol_l() functions convert the string in nptr to a long value. The strtoll() and strtoll_l() functions convert the string in nptr to a long long value. The strtoimax() and strtoimax_l() functions convert the string in nptr to an intmax_t value. The strtoq() function converts the string in nptr 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 determined by isspace(3) or isspace_l(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() and strtol_l() store the address of the first invalid character in *endptr. If there were no digits at all, however, strtol() and strtol_l() store the original value of nptr in *endptr. (Thus, if *nptr is not `\0' but **endptr is `\0' on return, the entire string was valid.) The strtol_l(), strtoll_l(), and strtoimax_l() functions take an explicit locale argument, whereas the strtol(), strtoll(), strtoimax(), and strtoq() functions use the current global or per-thread locale.

RETURN VALUES

The strtol(), strtol_l(), strtoll(), strtoll_l(), strtoimax(), strtoimax_l(), 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 variable 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 table. Function underflow overflow strtol() LONG_MIN LONG_MAX strtol_l() LONG_MIN LONG_MAX strtoll() LLONG_MIN LLONG_MAX strtoll_l() LLONG_MIN LLONG_MAX strtoimax() INTMAX_MIN INTMAX_MAX strtoimax_l() INTMAX_MIN INTMAX_MAX strtoq() LLONG_MIN LLONG_MAX

ERRORS

[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.

SEE ALSO

atof(3), atoi(3), atol(3), strtod(3), strtonum(3), strtoul(3), wcstol(3), xlocale(3)

STANDARDS

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. DragonFly 3.7 December 25, 2013 DragonFly 3.7

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