fgets() function atomatically breaking line when string is printed

Question

#include <stdio.h>

void main () {
    char str[5];
    fgets(str, sizeof(str), stdin);
    printf("%s.", str);
}

I wrote this simple code in C, and I'm trying to print a string and a dot in a single line, but whenever I enter a string with 3 or less characters, the output has a line break after the string.

Input:

abc

Output:

abc
.

If I enter something with exactly 4 characters, the output is as I want, without the line break.

I've tried using the gets() and scanf() functions and they worked well, but I cannot use them.

Does someone know why it happens and a solution?

Did you read the documentation of `fgets`? If yes, read again **carefully**. If not: read carefully. — too honest for this site, Jun 17 '16 at 01:54
[Advice on removing the newline that `fgets` puts in the buffer](https://stackoverflow.com/a/28462221/3386109) — user3386109, Jun 17 '16 at 02:24
"If I enter something with exactly 4 characters, the output is as I want" --> and the `'\n'` is waiting to be read by the _next_ `fgets()` call. But the program ends first, — chux - Reinstate Monica, Jun 17 '16 at 02:54

score 6 · Answer 1 · answered Jun 17 '16 at 01:57

The explanation to this issue is in the documentation of fgets:

Parsing stops if end-of-file occurs or a newline character is found, in which case str will contain that newline character.

That is precisely what happens in your case: str contains the input string "abc" followed by '\n', which gets printed between "abc" and dot '.'.

score 0 · Accepted Answer · answered Jun 17 '16 at 08:32

The issue is fgets() reads the newline char. You need to take out the newline character which is getting appended in you char array.

After fgets(str, sizeof(str), stdin); You can write below line to get rid of that newline character

str[strlen(str)-1]='\0'; or alternatively you can do like,

char * p=NULL;
p= strchr(str,'\n');
if(p!=NULL)
{
 *p='\0';
}

fgets() function atomatically breaking line when string is printed

2 Answers2