#include <stdio.h>#include <stdlib.h>#include <string.h>#include <stdint.h>struct FileHeader { unsigned long magic_number; unsigned long fileLength;} header;void performFileIO(const char *infile){ FILE *FileIn, *FileOut; char inBuffer[BUFSIZ]; char tempBuffer[4]; int position = 0, len; // marks the header of a file found within the input file const unsigned char pattern[] = {0xFF, 0x57, 0x50, 0x43}; // properly open the binary file for reading FileIn = fopen(infile, "rb"); if (FileIn == NULL) { printf("The file could not be opened, please check your file and location before trying again.\n"); exit(1); } printf("Enter the name and path for the output file: "); gets(inBuffer); FileOut = fopen(inBuffer, "w+b"); // position the file marker at the beginning of file fseek(FileIn, 0, SEEK_SET); while (!feof(FileIn)) { position++; if (fgetc(FileIn) == pattern[0]) { tempBuffer[0] = pattern[0]; if (fread(tempBuffer + 1, sizeof(char), 3, FileIn) != 3) { printf("Error reading file.\n"); exit(1); } if (memcmp(pattern, tempBuffer, sizeof(pattern)) == 0) { printf("Match Found.\n"); // now that match is found load pattern into struct header.magic_number = pattern; fseek(FileIn, 21, SEEK_CUR); // find the file size // four byte size of file found if (fread(tempBuffer, sizeof(char), 4, FileIn) != 4) { printf("Match found but fatal error reading file.\n"); exit(1); } // after finding filesize load it into struct header.fileLength = tempBuffer; // retract to the pattern header fseek(FileIn, -25, SEEK_CUR); // read the full - whole file loaded into the structure if (fread(&header, sizeof(struct FileHeader), 1, FileIn) != 1) { printf("Match found but fatal error reading of size struct.\n"); exit(1); } // present for output to user specified file fwrite(&header, sizeof(struct FileHeader), 1, FileOut); break; continue; } fseek(FileIn, -3, SEEK_CUR); } } // close the files and at the same time flush the buffers fclose(FileIn); fclose(FileOut);}// program entry pointint main(int argc, char *argv[]){ char buffer[BUFSIZ]; printf("Please enter the name and path of the binary file: "); gets(buffer); performFileIO(buffer); printf("\n Done!\n Press enter to exit\n"); getchar(); return 0;}