fprintf in c

If you are searching for fprintf in c you are at the right blog post. Each and every piece of information about fprintf in c is explained in this blog post.

What is fprintf in c programming?

fprintf function in c is used to format the output to a file instead of stdout console.

It is used to write a set of characters to a file. Instead of printing some characters to the console, we can make use of fprintf to write the output to the file.

The character ‘f’ in fprintf stands for formatted. The data formatted in such a way that the user can understand it or read it in an easy way.

It returns the number of characters written.if any error occurs it returns negative value(-1).

fprintf in c found in standard input output library that is stdio.h.

prototype

int fprintf(FILE *file_pointer, const  char *format_string,.......);

Parameters for fprintf

Here FILE* is a file pointer which points to a file where output is to be written. Format string describes the output format. Variables are specified like in printf to use their values.

Return value of fprintf

fprintf returns an int value i.e. the number of characters written on to a file. If it fails to execute then returns -1.

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Example program for fprintf in c

#include <stdio.h>
int main()
{
 FILE *fpointer;
 fpointer=fopen("abc.txt","w");
 fprintf(fpointer,"Scholarsoul.com\n");
 fclose(fpointer);
 return 0;
}

Code explanation

fprintf is called by passing the text value to be printed and a file pointer. This file pointer points to the file which is being opened for a specific task.

fprintf() Man page

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Differences between fprintf and fgetc in c

fgetc function in c is used to read a character from a file.fprintf function puts the character to a file.

Both functions take one character at a time.

fprintf is an output function where as fgetc is an input function.

Both functions take pointer to advance.

As fgetc is input function it takes only one argument whereas fprintf is an output function so it takes two arguments. As we can see in their prototypes,

int fgetc(FILE *strm);

int fprintf(FILE *strm,const char *formt,...);

fgetc the function returns the character read as unsigned char otherwise error. Whereas fprintf the function returns a total number of characters written into the file otherwise negative number as an error.

Look at the below table

fprintf in c	fgetc in c
It sends formatted data to a specified file.	Used to read character from a file
It takes one character at a time	It also takes one character at a time.
Output function	Input function
Uses pointer	Uses pointer
Takes two or more arguments.	Takes only one argument
int fprintf(FILE *strm,const char *formt,...);	int fgetc(FILE *strm);

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Differences between fprintf and fscanf in c

fscanf function reads formatted data from a stream. fprintf function puts formatted data into a file.

Both functions requires a pointer which points to a file.

fprintf function is used as output function .fscanf function is used as input function.

As both are file handling i/o functions,they have same prototype.

fscanf function returns the input data which are matched or zero on matching failure. whereas fprintf the function returns a total number of characters written or a negative number on error.

fscanf functions remove all the whitespaces before reading the characters. Whereas fprintf function does not remove any whitespace.

Look at the below table

fprintf in c	fscanf in c
Writes formatted data to a file	Reads formatted data from stream
Needs pointer	Needs pointer
Output function	Input function
int fprintf(FILE *strm,const char *formt,...);	int fscanf(FILE * fpointer, conast char *frmt[argmt,...]);
Returns negative number on error	Returns zero on error
Does not remove any whitespaces	Removes all whitespaces before seek.

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Differences between fprintf and putw in c

putw function is used to write integer value into a file. whereas fprintf function is used to write formatted data into a file.

Both functions needs file pointer.

Both are output functions.

Prototype is as below,

putw(int num,FILE *fpointer);

int fprintf(FILE *strm,const char *formt,...);

In putw function pointer is used to write numbers into file. Whereas in fprintf pointer is used for seek operation.

Look at the below table

fprintf in c	putw in c
Used to write formatted data into a file	Used to write integer value to a file
Needs pointer	Needs pointer
Output function	Output function
int fprintf(FILE *strm,const char *formt,...);	putw(int num,FILE *fpointer);
Returns toatal number of characters otherwise negative number	Returns 0 after successful completion otherwise negative number

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People also ask for

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How can I print ‘hello world’ in C without using printf and puts in the program?

//we have written hello scholar soul instead of hello world.
#include<stdio.h>
#include<stdlib.h>
#include<unistd.h>
int main(int argc, char const *argv[])
{
	fprintf(stdout,"Hello Scholar soul!");
	return 0;
}

Code explanation

We can print a statement in c without using printf and puts functions as seen in above code. Here with the help of fprintf function we are putting statement “Hello scholar soul!” into a file. Only difference here is we are using one pointer named stdout. stdout is a file descriptor associated with standard output console.

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