fgets always reads 3 junk chars at the first line of a file

Question

I'm reading a text file with this format:

DUMMY,0000000000000100100000000000000000
JOHNDOE,0000000000000010000000100000000100
FOO,0000000000000000000000000100000000
BAR,1000000100000000000000000000000000

When using fgets like this:

while (fgets(line, linelength, stream) != NULL) { 
...
}

It always get three junk characters in the first line. I tried deleting the first line with a plain text editor just to test there's nothing like non-printable characters before the text, with no results. They are always the same three chars. The first line, when readed by fgets looks like this in the Visual Studio debugging console:

ï»¿DUMMY,0000000000000100100000000000000000

When used printf to show on the terminal, it looks like this:

∩╗┐DUMMY,0000000000000100100000000000000000

As said above, if I delete the first line of the input file, then the next line also has the same characters:

∩╗┐JOHNDOE,0000000000000010000000100000000100

Funny thing, if I put an empty line as the first one in the input file, everything seems to be OK.

And how do you create or edit this text file? How do you save it? Do you possibly save it as UTF-8 with [BOM](https://en.wikipedia.org/wiki/Byte_order_mark)? — Some programmer dude, May 19 '20 at 14:24

chux - Reinstate Monica · Accepted Answer · 2020-05-19T14:41:09.523

Byte order mark @Some programmer dude

ï»¿DUMMY,0000000000000100100000000000000000
^^^

Instead of editing/saving the file as UTF-8, save the text file as a raw ASCII file.

Other possibility involves using an implementation specific fopen() - yet some OP code would help to explore that.

See also
How to Read/Write UTF8 text files in C? ,
C how to skip BOM when checking if x is at the start of a file,
Is it possible to prevent adding BOM to output UTF-8 file? (Visual Studio 2005) .

fgets always reads 3 junk chars at the first line of a file

1 Answers1