strtok

[New]

I have a String from a file in the form <number> <word>,<word>,< word>,<word>
<number>
when I try to tokenize it I store it in a char[] and tokenize it using
strtok(string, " ") and then tokenize the orignal string using
strtok(string," ,")

the first tokenization gives me only the first number and then NULL's
and the second tokenization gives me 1st char[]=<word> 2nd char[]=<word> 3rd
char[]=<word>
4th char[]=<word> <number>

What am I doing wrong?

[Dan Pop]

Re: strtok

In <412dae53_1@new s.iprimus.com.a u> "New" <a@a.co> writes:
[color=blue]
>I have a String from a file in the form <number> <word>,<word>,< word>,<word>
><number>
>when I try to tokenize it I store it in a char[] and tokenize it using
>strtok(strin g, " ") and then tokenize the orignal string using
>strtok(string, ",")
>
>the first tokenization gives me only the first number and then NULL's
>and the second tokenization gives me 1st char[]=<word> 2nd char[]=<word> 3rd
>char[]=<word>
>4th char[]=<word> <number>
>
>What am I doing wrong?[/color]

The proper sequence of strtok calls for your purpose is:

strtok(string, " ");
strtok(NULL, ",");
strtok(NULL, ",");
strtok(NULL, ",");
strtok(NULL, " ");
strtok(NULL, "");

Consider tokenising the whole string with a single sscanf call.

Dan
--
Dan Pop
DESY Zeuthen, RZ group
Email: Dan.Pop@ifh.de

[bowsayge]

Re: strtok

New said to us:
[color=blue]
> I have a String from a file in the form <number> <word>,<word>,< word>,<word>
> <number>
> when I try to tokenize it I[/color]
[...]

You need to change the delimiters string while you loop over the
tokens:

char str [] = "4116 black,10 feet,stationary ,none 18";
char * delim = " ";
char * ptr1 = 0;
char * ptr2 = 0;
int field = 0;
ptr1 = str;
while ((ptr2 = strtok(ptr1, delim))) {
ptr1 = 0;
delim = ",";
if (++field == 4) { delim = " "; }
printf ("token: %s\n", ptr2);
}

[Tim Hagan]

Re: strtok

"bowsayge" <bowsayge@nomai l.afraid.org> wrote in message
news:ZelXc.1327 9$2L3.1119@news read3.news.atl. earthlink.net.. .[color=blue]
> New said to us:
>[color=green]
> > I have a String from a file in the form <number> <word>,<word>,< word>,<word>
> > <number>
> > when I try to tokenize it I[/color]
> [...]
>
> You need to change the delimiters string while you loop over the
> tokens:
>
> char str [] = "4116 black,10 feet,stationary ,none 18";
> char * delim = " ";
> char * ptr1 = 0;
> char * ptr2 = 0;
> int field = 0;
> ptr1 = str;
> while ((ptr2 = strtok(ptr1, delim))) {
> ptr1 = 0;
> delim = ",";
> if (++field == 4) { delim = " "; }
> printf ("token: %s\n", ptr2);
> }
>[/color]

If <word> is a single word, then this will work:

#include <stdio.h>
#include <string.h>

int main(void)
{
char s[] = "123 abc,def,ghi,jkl 456";
char *d = " ,";
char *p = s;
char *t;

printf("string: %s\n", s);
while (t = strtok(p, d))
{
printf("token: %s\n", t);
p = NULL;
}
return 0;
}

--
Tim Hagan