How to use fgets in this code?

Question

I need to count words from a text file. For example the file includes

"Hans Mustermann Ingo Mustermann Trude Musterfrau Trude Mustermann Gerda Muster"

when I search for Trude Mustermann it should show 5 hits.

My code runs only one line I guess and then it stops.

#include <stdio.h>
#include <stdlib.h>

int main(int argc, char const *argv[])
{   
int num =0;
char word[100];
char *string;

FILE *in_file = fopen("test.txt", "r"); //reading the words

if (in_file == NULL)
{
    printf("Dataerror\n"); //if word not found
    exit(-1);
}

else {
    fscanf("%s", word);

    while(!feof(in_file))//search for the word

    {
        fscanf(in_file,"%s", string);
        if(!strstr(string , word))//if hit a word
        num++;
    }

    printf( "%d Hit \n" ,num );
}
return 0;
}

I have tried using scanf("%[^\n]",word);getchar(); but that did not help.

Answer 1

That’s was one of my test to learn C, long time ago. As I remember, you need something like the following:

#define numWords 2
char * words[numWords] = {"Trude", "Mustermann"};
int counters[numWords] = {0, 0};

void CountWords(char * Buffer)
{
    char *p1=Buffer; 
    char *p2;
    char *p3;
    int i;
    int n=0;

    // initialize the counters
    memset(counters, 0x00, sizeof(counters));

    do
    {
        p2=NULL;
        for (i=0; i < numWords; i++)
        {
            p3=strstr(p1, words[i]);
            if (p3) // found a word 
            {
                // if p2 is null or p3 is before p2
                if (!p2 || p3 <= p2) 
                {
                    p2=p3;
                    n=i;
                }
            }
        }
        if (!p2) break; // no more words
        counters[n]++;
        p1=p2+strlen(words[n]);
    } while (TRUE);

    for (i=0; i < numWords; i++)
    {
        printf("The word '%s' appears %5d time/s\n", words[i], counters[i]); 
    }
}

To test that function:

CountWords("Hans Mustermann Ingo Mustermann Trude Musterfrau Trude Mustermann Gerda Muster");

If you want to test from a text file, then use the following:

// To read from a file, I'd suggets to read the whole file in memory, 
// and search in that buffer.
if (_sopen_s(&FD, "test.txt", O_RDONLY | O_BINARY, _SH_DENYNO, _S_IREAD)) 
{
    return; // file not found
}
fSize=_lseek(FD, 0, FILE_END); // get file's size
_lseek(FD, 0, FILE_BEGIN); // rewind it
// Allocate memory to read the file's content
if ((Buffer = (char *)malloc(fSize+1)) == NULL) 
{
     _close(FD);
     return; // Not enough memory
}

__try
{
    i=_read(FD, Buffer, fSize);
    _close(FD);
    if (i != fSize) return; // error reading the file
    Buffer[fSize]=NULL;
    CountWords(Buffer);
}
__finally
{
    free(Buffer);
}

To test from the file, you need to include the following header files.

#include <stdio.h>
#include <fcntl.h>
#include <sys/stat.h>
#include <io.h>
#include <share.h>