The more you learn, the less you pay. What this actually means is that when it reads a normal character in the file, it will return a value suitable for storing in an unsigned char (basically, a number in the range 0 to 255). Only few modifications included. }. Lets understand this with the help of an example. So far, we have learned file operations on text files, what if the files are binary (such as .exe file). It wont create cz u r opening a file in read mode. A) a+ mode always appends new data to the end of existing content. Dynamic Memory Allocation in C using malloc(), calloc(), free() and realloc(). On the other hand, when you're at the very end of the file, you can't get a character value--in this case, fgetc will return "EOF", which is a constnat that indicates that you've reached the end of the file. C File Management-1 FILE is a keyword in C for representing files and fp is a variable of FILE type. ch==EOF checks for end of file and while loop stops or exits. char *s Array of char. Here "r" is File open mode. fclose(fp); The file is opened using fopen() function, while opening you can use any of the following mode as per the requirement. Mode: the actual date-type of the data-structure that the OS will use access data from a file. s: Array of characters to store strings. B) Closing a file clears Buffer contents from RAM or memory. FILE *fopen(const char *filename, const char *mode); FILE *fp = fopen("stud.dat", "r"); /* Read from file */ Write a program to retrieve data from a student data file.if(typeof ez_ad_units!='undefined'){ez_ad_units.push([[728,90],'howtoforge_com-medrectangle-4','ezslot_1',108,'0','0'])};if(typeof __ez_fad_position!='undefined'){__ez_fad_position('div-gpt-ad-howtoforge_com-medrectangle-4-0')}; /* Program to retrieve data from a student data file */ stream Specifies output file It is a type name defined in stdio.h. (B) FILE is a structure and fp is a pointer to the structure of FILE type(C) FILE is a stream(D) FILE is a buffered streamAnswer: (B)Explanation: fp is a pointer of FILE type and FILE is a structure that store following information about opened file. Opening a File c) "binary" a) A character string containing the name of the file & the second argument is the mode for example: The address of the first character is stored in pointer fp. If we want to keep records permanently, save them in a file. This code will check whether the file has opened successfully or not. By Chaitanya Singh | Filed Under: c-programming. Both are used to write in a file. b) Both connected to screen always d) None of the mentioned. Bank account system in C using File handling, Error handling during file operations in C/C++, Employee Record System in C using File Handling, Bookshop management system using file handling, Four File Handling Hacks which every C/C++ Programmer should know, Complete Interview Preparation- Self Paced Course. Because fget() function takes care of returning one by one character from file. a+ Open for append; open for update at the end of the file, or w+ is a mode used to open a text file for update (i. e., writing and reading), discard previous contents if any. You can append or add new content to the existing contents. Come write articles for us and get featured, Learn and code with the best industry experts. fscanf("format specifier",variables, fp); B) fprintf(fp,count,"format specifier",variables); FILE *fp = fopen("emp.dat", "a+"); /* Read and Write on file */. d) "01", a) create text file for writing, discard previous contents if any Checks whether the position marker in the file given by its handle is at the end-of-file. fprintf(fp, "%d %s %d %d %d\n", sno, name, sub1, sub2, sub3); To read the file, we must open it first using any of the mode, for example if you only want to read the file then open it in r mode. The second argument is the file to write to. Below mentioned is a simple example of writing into a binary file. File Pointer points to: First character of the file. 2022 Studytonight Technologies Pvt. Which of the following is data type of file pointer? Fclose(fp); fclose(stud); fcloseall(); Sends formatted output to a stream. 7) If a FILE pointer is NULL what does it mean.? _____removes the named file, so that a subsequent attempt to open it will fail. A lot of these details are system-specific though, so depending on the OS, the b) A character string containing the name of the user & the second argument is the mode c) Rom Above two programs are same, but the second program contains a highlighted statement (FILE *fp = fopen(stud.dat, a+); ) and a few modifications like fprintf, fp. 13) Choose a correct statement about C file mode "a". fread() is also used in the same way, with the same arguments like fwrite() function. clrscr(); Argument What It Is/Does definition may differ. Argument What It Is/Does The Opening modes are mentioned in the table for opening modes above. 12) Choose a correct statement about C file mode "w+". Rewind(stream) is equivalent to fseek(stream, 0L, SEEK_SET) char name[10]; Fscanf(fp, %d %s %d %d %d, &sno, name, &sub1, &sub2, &sub3); While opening a file, you need to specify the mode. str str represents the array, in which string is stored. 3. fscanf(fp,"format specifier",variables); Certifications Boost Confidence. This process is known as file control/file management/file organization. fp = fopen(source.txt, rb); With the help of rb option you can open file in read mode with binary which means if file contents are written in binary than you can read that file only with this option i.e. Certifications Boost Confidence. b) char * type "w" is used for writing a file. eg. The fopen() function creates a new file when the specified file doesnt exist and if it fails to open file then it returns NULL. MCQs to test your C++ language knowledge. fpr is pointer to file, which is going to be read. 9) Choose a correct statement about C file "R" mode operation using fopen. Run C++ programs and code examples online. c) struct type In this program, we have created two FILE pointers and both are refering to the same file but in different modes. B) EOF is End Of File. Char *fgets(char *s, int n, FILE *stream); Reads/writes a character from a stream. main() B) a+ mode creates a new file if not found or existing. Please use ide.geeksforgeeks.org, This feature is only available to subscribers. B) Binary mode is just reading or writing in bytes instead of integers, characters or strings. The mode string used in calls to fopen, is one of the following values: r Open for reading only a) int type Here, *fp is the FILE pointer (FILE *fp), which will hold the reference to the opened(or created) file. Go through Certifications CENTER. c) Both connected to screen by default Answer: A Based on the mode selected during file opening, we are allowed to perform certain operations on the file. Questions from Previous year GATE question papers, UGC NET Previous year questions and practice sets. We should not read after a write to a file without an intervening call to fflush(), fseek() or rewind(). It is not possible to combine two or more file opening mode in open () method. fread() and fwrite() functions are used to read and write is a binary file. fpr: Pointer to the input file. { Go through, C MCQ Questions and Answers on File Operations IO. Ltd. except that rewind clears the end-of-file and error indicators, while fseek only clears the end-of-file indicator. The function fgets/fputs gets/puts a string(of size n bytes) on the file pointed to by stream and returns end-of-file on error. Because they accept pointers, you can also use these functions with other data structures; you can even write structs to a file or a read struct into memory. fopen () will return a null pointer instead. Why I used if(fgets(str, 10, fpr)==NULL as a logic to determine end of the file? A) "a" is for append operation. Closes the file pointed to by fp & returns 0 on success, EOF is returned in case of error. It is a macro to return nonzero if end-of-file has been reached on the stream. File Pointer points to: last character of the file. Answer: C Hence, when you open a file in Append(a) mode, the cursor is positioned at the end of the present data in the file. Writing a File Sitemap. Here we have used this logic because fgets returns NULL when there is no more records are available to be read. 19) What is the Cfunction used tomove current pointer to the beginning of file.? getc() and putc() are the simplest functions which can be used to read and write individual characters to a file. Here we will discuss how to read and write strings into a file. If there is any error while opening a file, fopen will return? As an argument you must provide a pointer to the file that you want to close. C) a+ mode allows reading also. Returns the number of bytes output or EOF in case of error. Ptr Pointer to any object; the data written begins at ptr FPUS writes content back to File. In C language, we use a structure pointer of file type to declare a file. writing if the file does not exist. Size_t fwrite(const void *ptr, size_t size, size_t n, FILE*stream); Mode r: It is a read only mode, which means if the file is opened in r mode, it wont allow you to write and modify content of it. For Example: To open a file you need to use the fopen function, which returns a FILE pointer. r+ Open an existing file for update (reading and writing) c) Pointer to the structure defined in stdio.h size Length of each item of data It is what is typically termed an opaque data type, meaning it's typically declared as a file_name is the name of the file, which you want to open. B) If file is not found, new file is created. A) Memory (RAM) is limited in any computer. } stream Specifies output file In those cases, fopen will create a file if you specify file mode as "w", "w+", "a", or "a+" otherwise it will return 0, the NULL pointer. rb to read contents of file, Copyright 2012 2022 BeginnersBook . }while(toupper(ch) != 'N'); Open Certification Helper Popup Reset Popup. The file pointer for the stream is positioned at offset number of bytes calculated from the position specified by whence. d) create text file for update, do not discard previous contents if any. No explanation is given for this question. FILE *fp = fopen("emp.dat", "w"); /* Write to file */ Like Mode w, fopen() creates a new file if it file doesnt exist. Once you've opened a file, you can use the FILE pointer to let the compiler perform input and output functions on the file. Int fgetc/fputc(FILE *stream); These are equivalent to the above fgetc/fputc. { Answer: C fwrite(pointer, size, count, filepointer); count=1 usually. do{ Here is the same program, but included statements with a few modifications. Size Length of each item of data