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[ab-c]

I want to find if a particular line in File1(ptin) exists in File2(ptout).
If it aint existing then printf the line File1. I think the code is correct but I am getting blank lines. Please help me with the code.

ptin=fopen("check1.txt","r");
ptout=fopen(outfile,"r");

if(ptin!=NULL&&ptout!=NULL)
{
        while(fgets(text, MAX_LEN_SINGLE_LINE, ptin)!=NULL)
        {
	while(fgets(textchk, MAX_LEN_SINGLE_LINE, ptout)!=NULL)
	{
		char *a=strstr(text,textchk);
                                if(a!=NULL)
               		    puts(text);
		else
                                    continue;
	}//rewind(ptout);
        }
	 
}
else
        printf("File not found :(\n");

[tabstop]

Do you want to check that the lines match exactly, or just that one is contained in the other?

Anyway, you're printing the lines that match, as opposed to the ones that don't. And if there are blank lines in the input file, then I guess they'll show up here too.

In other words: I don't think it's quite clear what you're getting, and how that differs from what you're supposed to be getting?

[ab-c]

I dono why I am getting blank lines, probably because my logic in the code is wrong. I hope the example below solves your doubts.

File1.txt
aabb
ccdd
ddee
ffgg

File2.txt
aabbiikk
ccddlmno
kkkkkkkk
jjjjj


Output expected is:
ddee
ffgg

[tabstop]

fgets doesn't strip out the newline characters, so that's one reason.

Also, strstr looks for the second argument somewhere inside the first argument.

Also also, you're printing out everytime there is a match, not if there's no match anywhere in the file.

ETA: Almost forgot -- you really do need to rewind your file pointer.

[ab-c]

So can you give me a code where:
1. fgets() can be used and newline character is avoided?

[tabstop]

So can you give me a code where:
1. fgets() can be used and newline character is avoided?

No, because such a thing does not exist. You can, after you read it in with fgets, remove the last character (using something like if (foo[n]=='\n') foo[n]='\0'; where n is chosen appropriately) if it is a newline character.

[ab-c]

So then I use strstr() ?
Can u embed your previous reply in my code?