Question

The problem is – I’m trying to sort several lines using qsort, everything works in the outfile. Unfortunately valgrind gives me errors about not freeing some memory blocks.

At first I thought – I need to free(lines) but it is already there. What am I missing?

qsort(lines, linenumber, sizeof(char*), compare_string);
 for(c=0; c<linenumber; c++) {
    fputs(lines[c], outfile);
 }
 free(lines);

Answer 1

How did you assign memory to lines? If it is a two-dimensional array then you have to malloc each line separately in a for loop.

Do something like this-

for(counter=Max_lines;counter>0;counter--){
     free(lines[counter]);
}