CODEWITHSUNDEEP
cstringpointerstokenizestrtok
Thomas Holden
Thomas Holden

Reputation: 75

Strtok removes first character in token C

I have this little problem when trying to tokenize a string from a http request directed at my "home made" Http server.

Basicly I am using these lines of code to tokneize.

    token = strtok(bufptr, "\n");

    while(token != NULL){
        printf("%s \n", token);
        token = strtok(NULL, "\n");
    }

The problem is that for every token, the first character is removed from the tokenized string. How can I solve this?

I have tried copying the string, I have tried using strstr, but I have not yet succeded. I bet there is something pretty easy I am doing wrong.

Best regards.

Upvotes: 1

Views: 1598

Answers (4)

Thomas Holden
Thomas Holden

Reputation: 75

For anyone else that is having this problem. The HTTP protocol uses the \r\n delimiters after the header lines, and a CRLN for seperating the body from the header. CRLN is \r\n\r\n as I understood it.

From my searching around the web I did not find alot easy readable information about the protocol. Of course, you do have the RFCs.

Thanks for the help everybody. Btw, I could never figure out how to accept an answer.

Upvotes: 0

Thomas Holden
Thomas Holden

Reputation: 75

I got it working by using the \r\n as delimiter instead of only \n I did not think UNIX sent \r\n for newline, but seems that it does? Anyways, thanks.

Upvotes: 0

chux
chux

Reputation: 153457

You have a '\r' in the string. (@Alessandro Suglia)

 printf("%sx\n", "abc\r");  // x substituted for space

Prints:

 xbc

The '\r' (return) move the print position to the beginning of the line. Then 'x' overwrites 'a'. This appears as the OP observed "the first character is removed from the tokenized string".

Upvotes: 3

Dr. Debasish Jana
Dr. Debasish Jana

Reputation: 7118

This is working just fine:

char bufptr[] = "aaaa\nbbbb\ncccc\nddd";
char *token;
token = strtok(bufptr, "\n");

while(token != NULL){
    printf("%s \n", token);
    token = strtok(NULL, "\n");
}

output is:

aaaa 
bbbb 
cccc 
ddd

Upvotes: 0

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