Reading file using fscanf into array

Hi all,

I'm sure that I'm missing something silly, but either I'm not reading the file into the array correctly or I'm not outputting it correctly. I can see my program looping from my printf "Data scanned:" output to the screen, but I don't think I've properly populated my array "hold".

Any suggestions?

Code:

---

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

#define                NUM_THREADS                10
#define                MAX_LENGTH                10

void *read_files(void *cnt);

int main()
{
        int cnt;
        pthread_t p_thread[NUM_THREADS];
        char file[10] = "file1";

        for(cnt = 0; cnt < NUM_THREADS; cnt++)
                /* Returns 0 on successful creation of the thread */
                if(pthread_create(&p_thread[cnt], NULL, read_files, (void *)cnt) != 0)
                {
                        fprintf(stderr, "Error creating the thread");
                }
        for(cnt = 0; cnt < NUM_THREADS; cnt++)
        {
                /* Waits for p_thread[cnt] to finish. */
                pthread_join(p_thread[cnt], NULL);
        }
        fprintf(stdout, "All threads completed.\n");
        return 0;
}

void *read_files(void *cnt)
{
        size_t        c = 0;                /* Counter variable */
        int                d = 1;
        int                n = 0;
        char        hold[100];
        char        temp[10];
        char        filename[10] = "file";
       
        FILE *datain;                /* File to be opened */

        snprintf(filename, MAX_LENGTH, "%s%d", filename, cnt);       
        printf("Filename = %s \n", filename);
        /* Attempt to open file */
        datain = fopen(filename, "r");

        while (!feof(datain))
        {
                fscanf(datain, "%s", &hold[n]);                /* Not working */
                printf("Data scanned: %s\n", hold[n]);    /* Not outputting hold var */
                n++;
        }
        /* Close the files */
        fclose(datain);
}

---

It seems you are trying to read a string into a single character:

Code:

---

        char        hold[100];
        while (!feof(datain))
        {
                fscanf(datain, "%s", &hold[n]);                /* Not working */
                printf("Data scanned: %s\n", hold[n]);    /* Not outputting hold var */
                n++;
        }

---

If the input file looks like this:

line one
next line
last line
EOF

"hold" will end up as:

lnlast line

Do you understand why that is?

Ah, yes - I see this now.

What I want to do is read the full file, word by word, and write this into my buffer (hold).

Here I can have the program read through all the files, word by word, and output the word, but the end result - once I get these pieces figured out - is to create one file from the ten input files.

Code:

---

        while (fscanf(datain, "%s", hold) == 1)
                        {
                        printf("In the loop: %s\n", hold);
                        }

---

I guess I could create another array and then assign hold to this each time it reads a word, but I bet there's a more efficient and cleaner method. I'll keep working on it.

Thanks!

Maybe check that the function works for one file WITHOUT using threads to being with.

Threads going wrong add a whole new dimension to the problems you'll be facing, so it helps to know that the code works beforehand.