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Compare files

#include <stdio.h> #include <stdlib.h> int main(int argc, char *argv[]) { FILE *fp1, *fp2; char ch1, ch2, same; unsigned long j; if(argc!=3) { printf("Usage: compare <file 1> <file 2>\n"); exit(1); } /* open first file */ if((fp1 = fopen(argv[1], "rb"))==NULL) { printf("Cannot open first file.\n"); exit(1); } /* open second file */ if((fp2 = fopen(argv [2], "rb"))==NULL) { printf("Cannot open second file.\n"); exit(1); } j = 0; same = 1; /* compare the files */ while(!feof(fp1)) { ch1 = fgetc(fp1); if(ferror(fp1)) { printf("Error reading first file.\n"); exit(1); } ch2 = fgetc(fp2); if(ferror(fp2)) { printf("Error reading second file.\n"); exit(1); } if(ch1 != ch2) { printf("Files differ at byte number %lu", j); same = 0; break; } j++; } if(same) printf("Files are the same.\n"); if(fclose( fp1 ) == EOF) { printf("Error closing first file.\n"); exit(1); } if(fclose( fp2 ) == EOF) { printf("Error closing second file.\n"); exit(1); } return 0; }