Thread: using strtok with \n

Hi guys, I'm trying to figure out the problem with my C code below
implementing strtok(). I am trying to read in a CSV text file which
contains information separated by commas and \n newlines. In the CSV
file, the first line is filled with header info that I don't want to
store in my array. After the header info is the useful info, for
example:

loan_id,lender_id,borrower_id,principle_amt,intere st_rate,loan_status,loan_..balance,fco_discount,lo an_amt_type,int_rate_type,risk,property_addr,prope rt..y_city,property_st,property_zip,settlement_dat e
2445,44490,3332000,344123.22,5.9,default,301223.89 ,1.2,Regular,Fixed,
22,204 Main Street,Baltimore,MD,21076,Mar 30 2009
10446,1490,367000,246128.15,7.65,good,199009.43,3. 8,regular,ARM,
12,23309 Pinetree Road,Birmingham,AL,78995,Sep 09 2012
433905,33,277705,566909.04,7.65,default,209880.43, 3.8,Jumbo,ARM,33,905
Pacific Coast Highway,Malibu,CA,90254,Dec 01 2021


Each line of comma-separated info is separated by a \n character. Here
is my code:

Code:

************************************************************************** 
filecontent_p = filecontent;    //set the pointer to index 0 of array 


                filecontent_p = strtok(filecontent, "\n"); //skip 
first line 
                printf("filecontent_p = %s\n", filecontent_p); 


                n=0; 


                filecontent_p = strtok(NULL, ","); 
                printf("filecontent_p = %s\n", filecontent_p); 
                newloan[n].loan_id = atoi(filecontent_p); 
                printf("loan[%i].loan_id = %i\n", n, 
newloan[n].loan_id); 


                filecontent_p = strtok(NULL, ","); 
                printf("filecontent_p = %s\n", filecontent_p); 
                newloan[n].lender_id = atoi(filecontent_p); 
                printf("loan[%i].lender_id = %i\n", n, 
newloan[n].lender_id);

AND ON AND ON...
************************************************** *************************..*
filecontent_p is a pointer to my large array that will store the
information. I am able to read the first line containing the header
information using the first strtok() command. Any subsequent reads are
not possible. All the following filecontent_p reads after I read in
the header line result in NULLs. Where is the pointer pointing to that
it results in NULL reads? I thought it should point to the first
character of the next line that contains info. Any help would be
great. thanks!

> All the following filecontent_p reads after I read in
the header line result in NULLs. Where is the pointer pointing to that
it results in NULL reads? I thought it should point to the first
character of the next line that contains info. Any help would be
great. thanks!

Because you're tokening (is that a word?) the file into lines, and then using the same pointer to tokenize (I don't think that's a word ) into columns.

Why not read each line with fgets() and parse it with sscanf() or strtok()?
Rather than reading it all then tokening the newlines, and then the commas.

Code:

char line[256];

/* ... */

while(fgets(line, sizeof(line), fp) != NULL)
{
    /* parse line (it contains a csv record), you may want to chop the newline off (see the FAQ) */

}