filecopy.c

/* basic operations with files */

 /* pointer arithmetics:
  *
  * push(pointer, v) INDICATES *(pointer++) = v
  * pop(pointer) INDICATES *(--pointer)
  * (*++v)[0] INDICATES (**++v)
  *           INDICATES first char in v
  *           INDICATES name of string/vector v
  * likewise, *v[0] INDICATES **v
  *       and *v[n] INDICATES **(v + n)
  * returntype (*funct)(args) INDICATES a function funct with arguments args which returns...
  * char **argv INDICATES pointer to char pointer
  * int(*v)[len] INDICATES pointer "v" to a vector of "len" int elements
  * int *v[len] INDICATES vector "v" of "len" pointers to int elements
  * void *funct() INDICATES function "funct" that returns a pointer-to-void
  * void (*funct)() INDICATES pointer to a function "funct" that returns void
  *
  */

 /* useful characters: [] # */

 # include <stdio.h>

 void filecopy(FILE * orig, FILE * copy);

 int main(int argc, char * argv[])
    {
      FILE * file;
      while(--argc > 0) // length of file
      {
       if((file = fopen(*++argv, "r")) == NULL) // if the file is the last one in the batch...
          return 1; // ...exits successfully
       else
          {
           filecopy(file, stdout); // otherwise, copies another file
           fclose(file); // then closes it
          }
      }
     return 0; // exits
    }

void filecopy(FILE * orig, FILE * copy)
    {
     int ch;
     //while((ch = getchar(orig)) != EOF) // BOOK VERSION, generates compiling error
     while((ch = getchar()) != EOF) // copies chars until the end of file
    putc(ch, copy);
    }