Well as all of you can see in previous tutorial of function in c programming we try to cover all in-build function in c not just only c but also other programming language like python, javascript, SQL, and other languages.
List of function program in c programming language
In this tutorial you can find all the function program in c and also learn about HOW TO USE IN-BUILD FUNCTION IN C with program example with explanation for these programs.
Check out our list of function program in c
fflush() function in c programming is use to flushes the contents of output to given file.
#includeOut for this code snippet comes in different order.<stdio.h> int main() { fprintf(stdout, "This is to stdout. "); fprintf(stderr, "This is to stderr. "); fprintf(stdout, "This is also to stdout. "); }
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| fflush function program in c |
The reason behind for this random order is buffered of any file in computer.
Well by default stdout is newline-buffered and on the other hand stderr is unbuffered.
For stdout the content will be stored inside the temporary buffer so the output will be displayed when counters a newline or end of the file.
On the other hand stderr is not buffered the out will be written immediately.
That's why the stderr will be displayed first in upper program.
But if you want to displayed the standout output first the you have to flush the output with the fflush program in c.
#include<stdio.h> int main() { fprintf(stdout, "This is to stdout. "); // output stream immediately fflush(stdout); fprintf(stderr, "This is to stderr. "); fprintf(stdout, "This is also to stdout. "); // output stream immediately fflush(stdout); }
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| Output |
fscanf() function in c programming is used to read input from a file.
Well this function works same as the scanf() function in c programming but instead of read the given input in c program fscanf() function read the data from file.
Most of the arguments of fscanf() function in c are same as scanf() function.
This function return the number of value and complete the read operation or return the end of file EOF and -1 on error occurred.
#include<stdio.h> #include <stdlib.h> int main() { FILE *f; char Name[50]; int roll_num, chars; float mark; fp = fopen("records.txt", "r"); if(f == NULL) { printf("Error opening file\n"); exit(1); } printf("Testing fscanf() function: \n\n"); printf("Name:\t\tRoll\t\tMarks\n"); while( fscanf(f, "Name: %s\t\tRoll num: %d\t\tMarks: %f\n" , Name, &roll_num, &mark) != EOF ) { printf("%s\t\t%d\t\t%.2f\n", name, roll_no ,marks); } fclose(f); return 0; }
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| Output of c program |
ferror() function in C Programming language is used to identify the error in given c file.
C program for ferror()
In this tutorial you will learn about how to use the ferror() function and programing syntax.
Prototype :-
int ferror(FILE *filename);
FILE *filename
#include<stdio.h> #include <stdlib.h> int main() { FILE *fr; char str[100]; if((f=fopen("help.txt","r"))==NULL){ printf("Cannot open the file..."); //file is not exist program is terminated exit(1); } // Check if here is some error in the file if(ferror(f)) printf("print the Error to read the file\n"); else printf("No error\n"); printf("File content is--\n"); //print the strings until EOF is encountered while(!feof(fr)){ fgets(str,100,fr); //print the string printf("%s",str); } //remember to close the opened file fclose(f); return 0; }
In System library function in c use the command int system(const char *command) name or program name to the host environment and also executed command processor and returns the command after complete the task that is given in the c program.
#include <iostream>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>int main () { char command[50]; strcpy( command, "-l" ); system(command); return(0); }
This function list down the dir file with the help of c program
#include <stdio.h> #include <string.h>int main () { char command[50]; strcpy( command, "dir" ); system(command); return(0); }
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| system program in c |
Lab() Function in c programming gives the absolute value of the integer and it return the absolute value of the long integer argument.
Showing program will tell how you can use the LAB function in c programming.
Example Program For Lab() Function In C Programming
Parameters:-
Y − is a integral value.
Return Value:-
This lab function returns the absolute value of y.
LAB Function Program Example :-
#include <stdio.h>#include <stdlib.h> int main () { long int e,d; e = labs(64887L); printf("Value for e = %ld\n", a); d = labs(-1003080L); printf("Value for d = %ld\n", b); return(0); }
OUTPUT:-
Value for e = 64887 Value for d = 1003080
fput() function in c programming is a file string function which is used to print a string to the file.
fput() function use two arguments pointer one of them is used for string and other one for file.
A null terminated string pointed by str in to a file.A null character is not written into a given and at the time of success it returns the 0 and EOF or -1.
#include<stdio.h> #include<string.h> int main() { char str[50]; FILE *fp; fp = fopen("yourfile2.txt", "w"); if(fp == NULL) { printf("Error for opening file\n"); exit(1); } printf("Testing with the help of fputs() function: \n\n"); printf("To stop reading press Ctrl+Z in windows and Ctrl+D in Linux :"); while( gets(str) != NULL ) { fputs(str, fp); } fclose(fp); return 0; }
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| fput() program in C programming language |
