C/File/File Copy

Copy a file

<source lang="cpp">

1. include <stdio.h>
2. include <stdlib.h>

int main(int argc, char *argv[]) {

 FILE *from, *to;
 char ch;

 if(argc!=3) {
   printf("Usage: copy <source> <destination>\n");
   exit(1);
 }
 /* open source file */
 if((from = fopen(argv[1], "rb"))==NULL) {
   printf("Cannot open source file.\n");
   exit(1);
 }
 /* open destination file */
 if((to = fopen(argv[2], "wb"))==NULL) {
   printf("Cannot open destination file.\n");
   exit(1);
 }
 /* copy the file */
 while(!feof(from)) {
   ch = fgetc(from);
   if(ferror(from)) {
     printf("Error reading source file.\n");
     exit(1);
   }
   if(!feof(from)) fputc(ch, to);
   if(ferror(to)) {
     printf("Error writing destination file.\n");
     exit(1);
   }
 }
 if(fclose(from)==EOF) {
   printf("Error closing source file.\n");
   exit(1);
 }
 if(fclose(to)==EOF) {
   printf("Error closing destination file.\n");
   exit(1);
 }
 return 0;

}

      </source>

Copy a file in reverse order

<source lang="cpp">

1. include <stdio.h>
2. include <stdlib.h>

int main(int argc, char *argv[]) {

 long loc;
 FILE *in, *out;
 char ch;

 if(argc != 3) {
   printf("Usage: revcopy <source> <destination>.\n");
   exit(1);
 }
 if((in = fopen(argv[1], "rb")) == NULL) {
   printf("Cannot open input file.\n");
   exit(1);
 }
 if((out = fopen(argv[2], "wb"))==NULL) {
   printf("Cannot open output file.\n");
   exit(1);
 }
 /* find end of source file */
 fseek(in, 0L, SEEK_END);
 loc = ftell(in);
 /* copy file in reverse order */
 loc = loc-1; /* back up past end-of-file mark */
 
 while(loc >= 0L) {
   fseek(in, loc, SEEK_SET);
   ch = fgetc(in);
   fputc(ch, out);
   loc--;
 }
 fclose(in);
 fclose(out);
 return 0;

}

      </source>

Copy one file to another

<source lang="cpp">

1. include <stdio.h>
2. include <stdlib.h>

int main(int argc, char *argv[]) {

 FILE *in, *out;
 char ch;
 if(argc!=3) {
   printf("You forgot to enter a filename.\n");
   exit(1);
 }
 if((in=fopen(argv[1], "rb")) == NULL) {
   printf("Cannot open input file.\n");
   exit(1);
 }
 if((out=fopen(argv[2], "wb")) == NULL) {
   printf("Cannot open output file.\n");
   exit(1);
 }
 while(!feof(in)) {
   ch = getc(in);
   if(ferror(in)) {
     printf("Read Error");
     clearerr(in);
     break;
   } else {
     if(!feof(in)) putc(ch, out);
     if(ferror(out)) {
       printf("Write Error");
       clearerr(out);
       break;
     }
   }
 }
 fclose(in);
 fclose(out);
 return 0;

}

      </source>