size_of_elements
是一次讀取的大小,number_of_elements
是讀取的次數。
size_t fread(void *ptr, size_t size_of_elements, size_t number_of_elements, FILE *a_file);
size_of_elements
是一次寫入的大小,number_of_elements
是寫入的次數。
size_t fwrite(const void *ptr, size_t size_of_elements, size_t number_of_elements, FILE *a_file);
[dywang@dyw219 zzz]$ vim fileio4.c [dywang@dyw219 zzz]$ cat fileio4.c #include <stdio.h> int main( int argc, char *argv[] ) { FILE *fp1, *fp2; char ch; fp1 = fopen( argv[1], "rb" ); fp2 = fopen( argv[2], "wb" ); if( fp1 != NULL) { while ( fread( &ch, sizeof(ch), 1, fp1) != 0 ) fwrite( &ch, sizeof(ch), 1, fp2 ); } else { printf("File %s does not exist.\n", argv[1]); } fclose(fp1); fclose(fp2); return 0; }
[dywang@dyw219 zzz]$ gcc -o fileio4 fileio4.c
[dywang@dyw219 zzz]$ ./fileio4 fileio1 fileio1.bak
[dywang@dyw219 zzz]$ diff fileio1 fileio1.bak