asked on

strtok -- how to revert to original string after processing????(Sorry points are low!!)

I have a code that takes a two word string and searches through documents for occurences of each string and returns how many times each occured.... problem is when I enter the second txt file, the string has been tokenised, i.e. only the first string is passed through the other docs, how do I revert to the original string for processing of the other files??

Here is the code....(its a CGI/C script)
printf("%s%c%c\n",
"Content-Type:text/html;charset=iso-8859-1",13,10);
printf("<TITLE>Response</TITLE>\n");

lenstr = getenv("CONTENT_LENGTH"); /* Getting string from HTML page */

if(lenstr == NULL || sscanf(lenstr,"%ld",&len)!=1 || len > MAXLEN) /*verifying that string is valid*/
printf("<P>Error in invocation - wrong FORM probably.</P>");

else { /* begin ELSE */

fgets(input, len+1, stdin);
unencode(input+EXTRA, input+len, data ); /* use function unencode to get actual string */

for ( int i = 0; i < 3; i++)

{ // begin of opening each file

if((essay = fopen( names[i] , "r+")) == NULL )
{
fprintf(stderr, "Error opening files\n");
return 0;
}

entry = strtok ( data, " ");
//entry2 = strtok ( data, " ");

while (( entry != NULL) && ( strlen(entry) > 2))

{

while (((fscanf(essay, "%s", word) == 1)) )
// begin WHILE at fscanf

if (strcmp(entry, word) == 0)

count++;

printf("%s occurred %d times in %s<br>", entry, count, names[i]);

count = 0;

// fputs(entry, results);

entry = strtok(NULL, " ");

fseek(essay, 0, 0);

}

fclose(essay); /* closing text file */

} // on to next file
........ etc etc etc end of program

Rgds PeteG

gj62

You have to make a copy...

char *copyData;

copyData = malloc(strlen(data)*sizeof(char)+1);
strcpy(copyData,data);

....
Do whatever you need to, then "restore" data...
....

strcpy(data, copyData);

PeteG

ASKER

gi62,

Thats just what I want to do, but I'm still getting an error -- -- I think the problem might be at the declaration of 'data'
this is the error message
C:\Inetpub\wwwroot\cgi-bin\finalCGIsearch\cgi2Search.cpp(79) : error C2440: '=' : cannot convert from 'void *' to 'char *'

Here is the declaration section....

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

#include <stdlib.h>
#define MAXLEN 80
#define EXTRA 5 /* 4 for field name "data", 1 for "=" */
#define MAXINPUT MAXLEN+EXTRA+2 /* 1 for added line break, 1 for trailing NUL */

void unencode(char *src, char *last, char *dest) /* code for converting the string inputted back to its regular form */
{
for(; src != last; src++, dest++)
if(*src == '+')
*dest = ' ';
else if(*src == '%') {
int code;
if(sscanf(src+1, "%2x", &code) != 1) code = '?';
*dest = code;
src +=2; }
else
*dest = *src;
*dest = '\n';
*++dest = '\0';

}

int main(void)
{ /* begin program */

int count = 0; /* counters */
FILE *essay;
char *names[] = {"C:/Inetpub/wwwroot/cgi-bin/diabetes.txt", "C:/Inetpub/wwwroot/cgi-bin/stroke.txt", "C:/Inetpub/wwwroot/cgi-bin/stemcells.txt" };
char *lenstr; /* pointer to the string received from the HTML page */
char input[MAXINPUT]; /* input received from the HTML page */
long len;
char data[MAXINPUT]; /* the unencoded input from the HTML page */
char *copyData;
char word[40];

char *entry;

printf("%s%c%c\n",
"Content-Type:text/html;charset=iso-8859-1",13,10);

... regards

PeteG

ASKER CERTIFIED SOLUTION

gj62

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PeteG

ASKER

Thanks a mil, sorted, sorry again about the low points.

gj62

Thank you - points were fair for the question - no worries.