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diff --git a/man3/strtol.3 b/man3/strtol.3 deleted file mode 100644 index b6609b2..0000000 --- a/man3/strtol.3 +++ /dev/null @@ -1,321 +0,0 @@ -'\" t -.\" Copyright 1993 David Metcalfe (david@prism.demon.co.uk) -.\" and Copyright 2006 Michael Kerrisk <mtk.manpages@ganil.com> -.\" -.\" SPDX-License-Identifier: Linux-man-pages-copyleft -.\" -.\" References consulted: -.\" Linux libc source code -.\" Lewine's _POSIX Programmer's Guide_ (O'Reilly & Associates, 1991) -.\" 386BSD man pages -.\" Modified Sun Jul 25 10:53:39 1993 by Rik Faith (faith@cs.unc.edu) -.\" Added correction due to nsd@bbc.com (Nick Duffek) - aeb, 950610 -.TH strtol 3 2023-12-19 "Linux man-pages 6.7" -.SH NAME -strtol, strtoll, strtoq \- convert a string to a long integer -.SH LIBRARY -Standard C library -.RI ( libc ", " \-lc ) -.SH SYNOPSIS -.nf -.B #include <stdlib.h> -.P -.BI "long strtol(const char *restrict " nptr , -.BI " char **restrict " endptr ", int " base ); -.BI "long long strtoll(const char *restrict " nptr , -.BI " char **restrict " endptr ", int " base ); -.fi -.P -.RS -4 -Feature Test Macro Requirements for glibc (see -.BR feature_test_macros (7)): -.RE -.P -.BR strtoll (): -.nf - _ISOC99_SOURCE - || /* glibc <= 2.19: */ _SVID_SOURCE || _BSD_SOURCE -.fi -.SH DESCRIPTION -The -.BR strtol () -function converts the initial part of the string -in -.I nptr -to a long integer value according to the given -.IR base , -which must be between 2 and 36 inclusive, or be the special value 0. -.P -The string may begin with an arbitrary amount of white space (as -determined by -.BR isspace (3)) -followed by a single optional \[aq]+\[aq] or \[aq]\-\[aq] sign. -If -.I base -is zero or 16, the string may then include a -"0x" or "0X" prefix, and the number will be read in base 16; otherwise, a -zero -.I base -is taken as 10 (decimal) unless the next character -is \[aq]0\[aq], in which case it is taken as 8 (octal). -.P -The remainder of the string is converted to a -.I long -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 \[aq]A\[aq] in -either uppercase or lowercase represents 10, \[aq]B\[aq] represents 11, and so -forth, with \[aq]Z\[aq] representing 35.) -.P -If -.I endptr -is not NULL, -and the -.I base -is supported, -.BR strtol () -stores the address of the -first invalid character in -.IR *endptr . -If there were no digits at -all, -.BR strtol () -stores the original value of -.I nptr -in -.I *endptr -(and returns 0). -In particular, if -.I *nptr -is not \[aq]\e0\[aq] but -.I **endptr -is \[aq]\e0\[aq] on return, the entire string is valid. -.P -The -.BR strtoll () -function works just like the -.BR strtol () -function but returns a -.I long long -integer value. -.SH RETURN VALUE -The -.BR strtol () -function returns the result of the conversion, -unless the value would underflow or overflow. -If an underflow occurs, -.BR strtol () -returns -.BR LONG_MIN . -If an overflow occurs, -.BR strtol () -returns -.BR LONG_MAX . -In both cases, -.I errno -is set to -.BR ERANGE . -Precisely the same holds for -.BR strtoll () -(with -.B LLONG_MIN -and -.B LLONG_MAX -instead of -.B LONG_MIN -and -.BR LONG_MAX ). -.SH ERRORS -This function does not modify -.I errno -on success. -.TP -.B EINVAL -(not in C99) -The given -.I base -contains an unsupported value. -.TP -.B ERANGE -The resulting value was out of range. -.P -The implementation may also set -.I errno -to -.B EINVAL -in case -no conversion was performed (no digits seen, and 0 returned). -.SH ATTRIBUTES -For an explanation of the terms used in this section, see -.BR attributes (7). -.TS -allbox; -lbx lb lb -l l l. -Interface Attribute Value -T{ -.na -.nh -.BR strtol (), -.BR strtoll (), -.BR strtoq () -T} Thread safety MT-Safe locale -.TE -.SH STANDARDS -C11, POSIX.1-2008. -.SH HISTORY -.TP -.BR strtol () -POSIX.1-2001, C89, SVr4, 4.3BSD. -.TP -.BR strtoll () -POSIX.1-2001, C99. -.SH NOTES -Since -.BR strtol () -can legitimately return 0, -.BR LONG_MAX , -or -.B LONG_MIN -.RB ( LLONG_MAX -or -.B LLONG_MIN -for -.BR strtoll ()) -on both success and failure, the calling program should set -.I errno -to 0 before the call, -and then determine if an error occurred by checking whether -.I errno == ERANGE -after the call. -.P -According to POSIX.1, -in locales other than "C" and "POSIX", -these functions may accept other, -implementation-defined numeric strings. -.P -BSD also has -.P -.in +4n -.EX -.BI "quad_t strtoq(const char *" nptr ", char **" endptr ", int " base ); -.EE -.in -.P -with completely analogous definition. -Depending on the wordsize of the current architecture, this -may be equivalent to -.BR strtoll () -or to -.BR strtol (). -.SH CAVEATS -If the -.I base -needs to be tested, -it should be tested in a call where the string is known to succeed. -Otherwise, it's impossible to portably differentiate the errors. -.P -.in +4n -.EX -errno = 0; -strtol("0", NULL, base); -if (errno == EINVAL) - goto unsupported_base; -.EE -.in -.SH EXAMPLES -The program shown below demonstrates the use of -.BR strtol (). -The first command-line argument specifies a string from which -.BR strtol () -should parse a number. -The second (optional) argument specifies the base to be used for -the conversion. -(This argument is converted to numeric form using -.BR atoi (3), -a function that performs no error checking and -has a simpler interface than -.BR strtol ().) -Some examples of the results produced by this program are the following: -.P -.in +4n -.EX -.RB "$" " ./a.out 123" -strtol() returned 123 -.RB "$" " ./a.out \[aq] 123\[aq]" -strtol() returned 123 -.RB "$" " ./a.out 123abc" -strtol() returned 123 -Further characters after number: "abc" -.RB "$" " ./a.out 123abc 55" -strtol: Invalid argument -.RB "$" " ./a.out \[aq]\[aq]" -No digits were found -.RB "$" " ./a.out 4000000000" -strtol: Numerical result out of range -.EE -.in -.SS Program source -\& -.\" SRC BEGIN (strtol.c) -.EX -#include <errno.h> -#include <stdio.h> -#include <stdlib.h> -\& -int -main(int argc, char *argv[]) -{ - int base; - char *endptr, *str; - long val; -\& - if (argc < 2) { - fprintf(stderr, "Usage: %s str [base]\en", argv[0]); - exit(EXIT_FAILURE); - } -\& - str = argv[1]; - base = (argc > 2) ? atoi(argv[2]) : 0; -\& - errno = 0; /* To distinguish success/failure after call */ - strtol("0", NULL, base); - if (errno == EINVAL) { - perror("strtol"); - exit(EXIT_FAILURE); - } -\& - errno = 0; /* To distinguish success/failure after call */ - val = strtol(str, &endptr, base); -\& - /* Check for various possible errors. */ -\& - if (errno == ERANGE) { - perror("strtol"); - exit(EXIT_FAILURE); - } -\& - if (endptr == str) { - fprintf(stderr, "No digits were found\en"); - exit(EXIT_FAILURE); - } -\& - /* If we got here, strtol() successfully parsed a number. */ -\& - printf("strtol() returned %ld\en", val); -\& - if (*endptr != \[aq]\e0\[aq]) /* Not necessarily an error... */ - printf("Further characters after number: \e"%s\e"\en", endptr); -\& - exit(EXIT_SUCCESS); -} -.EE -.\" SRC END -.SH SEE ALSO -.BR atof (3), -.BR atoi (3), -.BR atol (3), -.BR strtod (3), -.BR strtoimax (3), -.BR strtoul (3) |