Bit of help with strings??

john_g83

Hello all, new user to c programming and am having difficulty with a little program I am trying to write. Basically what I have is a file which contains a list of words i.e:

tst.txt:

customer
customers
data
deactivate
deactivated
department
department
dept.

etc....

I want to read in each word from the file Individually, and assign each individual word to an individual element in an array.
the code I have so far is:

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

main()
{
int c;
FILE *in_file;
FILE *out_file;
FILE *out;

in_file = fopen ("thes1.txt", "r");

if( in_file == NULL )
printf("Cannot open %s for reading.\n");
else
out_file = fopen ("tst.txt", "w");
if( out_file == NULL )
printf("Can't open %s for writing.\n");
else {
while( (c = getc( in_file)) != EOF )
{
putc (c, out_file);
}

putc (c, out_file); /* copy EOF */
printf("File has been copied.\n");

}
fclose (in_file);
fclose (out_file);

out = fopen("tst.txt","r");

int zz=0;
char key2[20];

while(!feof(out))
{
fgets(key2,20,out);
printf("%s\n",key2);

}

}

this code will get each word Individually, but so far I have not been able to assign words to elements in an array, continiously getting errors about invalid conversions from char*. Any help would be greatly appreciated.
Kind Regards

NotMe

What are you trying to convert to? Do you have an array of char*?

theexis

Basically you should store a copy of key2 into an array:

char* words[maximum expected number of words];
int index = 0;

while(!feof(out))
{
    fgets(key2,20,out);
    printf("%s\n",key2);
    words[index++] = strdup(key2);
}

This is likely too simplified though since you'd probably need to dynamically allocate the array assuming you don't know how many words there will be.

Also, you'll need to clean up after you finish with the array to avoid memory leaks:

for (; 0 <= index; --index)
{
    free(words[index]);
}

Would you consider C++ though - STL would make this a lot cleaner.

john_g83

thanks for the replies.

theexis that snippet of code you gave me did exactly what I wanted, thanks a million. May be back soon with more stupid questions.
Regards
John