C Programming Code Examples C > File Operations Code Examples Copy a file in four debug level Copy a file in four debug level #include <stdio.h> #include <stdlib.h> /* DEBUG levels: 0: no debug 1: display byte read from source file 2. display byte written to destination file 3: display bytes read and bytes written */ #define DEBUG 2 int main(int argc, char *argv[]) { FILE *in, *out; unsigned char ch; /* see if correct number of command line arguments */ if(argc!=4) { printf("Usage: code <in> <out> <key>"); exit(1); } /* open input file */ if((in = fopen(argv[1], "rb"))==NULL) { printf("Cannot open input file.\n"); exit(1); } /* open output file */ if((out = fopen(argv[2], "wb"))==NULL) { printf("Cannot open output file.\n"); exit(1); } while(!feof(in)) { ch = fgetc(in); #if DEBUG == 1 || DEBUG == 3 putchar(ch); #endif ch = *argv[3] ^ ch; #if DEBUG >= 2 putchar(ch); #endif if(!feof(in)) fputc(ch, out); } fclose(in); fclose(out); return 0; }
