Learning how arrays, strings, structures, and pointers actually work will explain almost everything that's baffling you right now.
I am very aware of that, which reminds me of my early posts in this forum. Learning by "practice" related to real problem is better, like this one and the strtok() function...... Am I stubborn and offending if I insist C++
As I have the same feeling like most of the beginners that sometimes C++ is easier to catch than C, and I am not able to mix C with C++ code together in one program at this moment. Neither do I want get lost when trying to solve one problem, so that I asked for C++.
OK, here is a modified version of the code, and I hope it is a improved version from "professional views"
Which is what I need.
Thank you so much again!
When run it, segment fault.
What is wrong?
#include <stdio.h>
#include <stdlib.h>
const int max =20;
//****************************************************
// Input Matrix
//****************************************************
void inMatrixAA(int *AA, int row, int col)... (9 Replies)
Dear all,
I used debugger from C++ and these are the message I got:
Program received signal SIGSEGV, Segmentation fault.
0x00323fc0 in free () from /lib/tls/libc.so.6
(gdb) info s
#0 0x00323fc0 in free () from /lib/tls/libc.so.6
#1 0x00794fa1 in operator delete () from... (5 Replies)
Hi
some help read............
I'm getting a segmentation fault when I run an AIX COBOL/Db2 program.
I initiate the program from the command line, but it hangs, and then when I press enter it generates a segmantation fault and produces a core dump.
The box is running AIX software level ... (5 Replies)
Hi all
In the ltp-posix test,there is a case in open_posix_testsuite\conformance\interfaces\timer_gettime\speculative/6-1.c
I run the above code,it will has a segment fault, if I modify it to below,it works well
Anybody can tell me why? (1 Reply)
I´m writing this program in QNX , I`m kinda new to UNIX and programing in general, and when I try to run it it gives me the Memory Fault error. Can anyone help?
#include <stdio.h>
#include <fcntl.h>
void main(void)
{int a,ter;
char buf;
printf("a=");
scanf("%d",a);
ter=open... (6 Replies)
Hi,
Whether the following piece of code is placed in the read-only memory of code (text) segment or data segment?
char *a = "Hello";
I am getting two different answers while searching in google :( that's why the confusion is (7 Replies)
I always get segment fault, why? can sb help me and modify it, I have spend on much time on
#include <pthread.h>
#include <stdio.h>
#include <stdlib.h>
#include <sys/time.h>
#include <string.h>
#define MAX 10
pthread_t thread;
void *thread1()
{
int *a;
int i, n;
... (1 Reply)
Hello everybody,
I've been working on a program on my Linux box, after finished the code, i compile it with gcc -Wall option, so i can see what's wrong or unused.
The Walll output shows nothing, so there are no loose ends on the program.
I run the program on my system, and it works PERFECTLY.... (5 Replies)
Hi
I have struggling a week to fix a program , in the begining i got SIGBUS , but after many attempts still the program gets SIGSEGV segment fault , In bellow i post the seg fault log + source codes. would really appreciate if experts help me to fix this segment fault error. any advice is... (2 Replies)
Hello,
This function was copied into my code, which was compiled without error/warning, but when executed there is always Segmentation fault at the end after the output (which seems correct!):
void get_hashes(unsigned int hash, unsigned char *in)
{
unsigned char *str = in;
int pos =... (7 Replies)
Discussion started by: yifangt
7 Replies
LEARN ABOUT SUSE
strtok
STRTOK(3) Linux Programmer's Manual STRTOK(3)NAME
strtok, strtok_r - extract tokens from strings
SYNOPSIS
#include <string.h>
char *strtok(char *str, const char *delim);
char *strtok_r(char *str, const char *delim, char **saveptr);
Feature Test Macro Requirements for glibc (see feature_test_macros(7)):
strtok_r(): _SVID_SOURCE || _BSD_SOURCE || _POSIX_C_SOURCE >= 1 || _XOPEN_SOURCE || _POSIX_SOURCE
DESCRIPTION
The strtok() function parses a string into a sequence of tokens. On the first call to strtok() the string to be parsed should be specified
in str. In each subsequent call that should parse the same string, str should be NULL.
The delim argument specifies a set of characters that delimit the tokens in the parsed string. The caller may specify different strings in
delim in successive calls that parse the same string.
Each call to strtok() returns a pointer to a null-terminated string containing the next token. This string does not include the delimiting
character. If no more tokens are found, strtok() returns NULL.
A sequence of two or more contiguous delimiter characters in the parsed string is considered to be a single delimiter. Delimiter charac-
ters at the start or end of the string are ignored. Put another way: the tokens returned by strtok() are always nonempty strings.
The strtok_r() function is a reentrant version strtok(). The saveptr argument is a pointer to a char * variable that is used internally by
strtok_r() in order to maintain context between successive calls that parse the same string.
On the first call to strtok_r(), str should point to the string to be parsed, and the value of saveptr is ignored. In subsequent calls,
str should be NULL, and saveptr should be unchanged since the previous call.
Different strings may be parsed concurrently using sequences of calls to strtok_r() that specify different saveptr arguments.
RETURN VALUE
The strtok() and strtok_r() functions return a pointer to the next token, or NULL if there are no more tokens.
CONFORMING TO
strtok()
SVr4, POSIX.1-2001, 4.3BSD, C89, C99.
strtok_r()
POSIX.1-2001.
BUGS
Be cautious when using these functions. If you do use them, note that:
* These functions modify their first argument.
* These functions cannot be used on constant strings.
* The identity of the delimiting character is lost.
* The strtok() function uses a static buffer while parsing, so it's not thread safe. Use strtok_r() if this matters to you.
EXAMPLE
The program below uses nested loops that employ strtok_r() to break a string into a two-level hierarchy of tokens. The first command-line
argument specifies the string to be parsed. The second argument specifies the delimiter character(s) to be used to separate that string
into "major" tokens. The third argument specifies the delimiter character(s) to be used to separate the "major" tokens into subtokens.
An example of the output produced by this program is the following:
$ ./a.out 'a/bbb///cc;xxx:yyy:' ':;' '/'
1: a/bbb///cc
--> a
--> bbb
--> cc
2: xxx
--> xxx
3: yyy
--> yyy
Program source
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
int
main(int argc, char *argv[])
{
char *str1, *str2, *token, *subtoken;
char *saveptr1, *saveptr2;
int j;
if (argc != 4) {
fprintf(stderr, "Usage: %s string delim subdelim
",
argv[0]);
exit(EXIT_FAILURE);
}
for (j = 1, str1 = argv[1]; ; j++, str1 = NULL) {
token = strtok_r(str1, argv[2], &saveptr1);
if (token == NULL)
break;
printf("%d: %s
", j, token);
for (str2 = token; ; str2 = NULL) {
subtoken = strtok_r(str2, argv[3], &saveptr2);
if (subtoken == NULL)
break;
printf(" --> %s
", subtoken);
}
}
exit(EXIT_SUCCESS);
} /* main */
SEE ALSO index(3), memchr(3), rindex(3), strchr(3), strpbrk(3), strsep(3), strspn(3), strstr(3), wcstok(3)COLOPHON
This page is part of release 3.25 of the Linux man-pages project. A description of the project, and information about reporting bugs, can
be found at http://www.kernel.org/doc/man-pages/.
GNU 2008-10-29 STRTOK(3)