fopen - displaying contents of a file on monitor in C -


i'm trying recreate program saw in class. teacher made file 10 lines, showed file indeed created, , displayed contents. code doesn't work reason, prints looks a"=" million times , exits.

my code:

void main() {     file* f1;     char c;     int i;     f1=fopen("essay 4.txt","w");     for(i=0;i<10;i++)         fprintf(f1," essay deserves 100!\n");         {         c=getc(f1);         putchar(c);     }while(c!=eof); }

what problem? far can see did in example given.

the flow such:

  • you create file (reset empty file if exists). that's "w" mode does.
  • then write stuff. note file position considered @ end, writing moves file position.
  • now try read from end. first thing read eof already. indeed, when try program on mac, single strange character 1 expect fact you're using do { } while. suggest instead like: for (c = getc(f1); c != eof; c = getc(f1)) { putchar(c) } or similar loop.
  • but also, reading should fail anyway because file mode "w" (write only) instead of "w+".

so need 2 things:

  • use file mode "w+".
  • reset file position beginning of file after writing it: fseek(f1, 0, seek_set);.

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