• Dandyvica (43/43) Sep 20 2015 Hi all,
• Daniel =?UTF-8?B?S296w6Fr?= via Digitalmars-d-learn (9/64) Sep 20 2015 V Sun, 20 Sep 2015 20:17:36 +0000
• crimaniak (17/30) Sep 22 2015 CR/LF can be interpreted as line _dividers_, so if you have CR or

Dandyvica <dandyvica gmail.com> writes:

Hi all,

I can't explain to myself this weird behavior:

void main(string[] argv)
{
	char[] line;
	auto fh = File(argv[1]);
	while (!fh.eof) {
		writef("before readln eof=%s, ", fh.eof);
		fh.readln(line,std.ascii.newline);
		writefln("line=<%s>, after readln eof=%s",chomp(line), fh.eof);
	}
	fh.close();
}

My file is made of 10 lines:


cat numbers.txt
1
2
3
4
5
6
7
8
9
10

╰─$ wc -l numbers.txt
10 numbers.txt

When run:

before readln eof=false, line=<1>, after readln eof=false
before readln eof=false, line=<2>, after readln eof=false
before readln eof=false, line=<3>, after readln eof=false
before readln eof=false, line=<4>, after readln eof=false
before readln eof=false, line=<5>, after readln eof=false
before readln eof=false, line=<6>, after readln eof=false
before readln eof=false, line=<7>, after readln eof=false
before readln eof=false, line=<8>, after readln eof=false
before readln eof=false, line=<9>, after readln eof=false
before readln eof=false, line=<10>, after readln eof=false
before readln eof=false, line=<>, after readln eof=true

I can't explain why eof is not set to true after reading the last 
line ?!

Last DMD 2.68.1.0, Linux Mint 17.2.


Thanks for any clue.

Daniel =?UTF-8?B?S296w6Fr?= via Digitalmars-d-learn writes:

V Sun, 20 Sep 2015 20:17:36 +0000
Dandyvica via Digitalmars-d-learn <digitalmars-d-learn puremagic.com>
napsáno:

 Hi all,
 
 I can't explain to myself this weird behavior:
 
 void main(string[] argv)
 {
 	char[] line;
 	auto fh = File(argv[1]);
 	while (!fh.eof) {
 		writef("before readln eof=%s, ", fh.eof);
 		fh.readln(line,std.ascii.newline);
 		writefln("line=<%s>, after readln
 eof=%s",chomp(line), fh.eof); }
 	fh.close();
 }
 
 My file is made of 10 lines:
 
 
 cat numbers.txt
 1
 2
 3
 4
 5
 6
 7
 8
 9
 10
 
 ╰─$ wc -l numbers.txt
 10 numbers.txt
 
 When run:
 
 before readln eof=false, line=<1>, after readln eof=false
 before readln eof=false, line=<2>, after readln eof=false
 before readln eof=false, line=<3>, after readln eof=false
 before readln eof=false, line=<4>, after readln eof=false
 before readln eof=false, line=<5>, after readln eof=false
 before readln eof=false, line=<6>, after readln eof=false
 before readln eof=false, line=<7>, after readln eof=false
 before readln eof=false, line=<8>, after readln eof=false
 before readln eof=false, line=<9>, after readln eof=false
 before readln eof=false, line=<10>, after readln eof=false
 before readln eof=false, line=<>, after readln eof=true
 
 I can't explain why eof is not set to true after reading the last 
 line ?!
 
 Last DMD 2.68.1.0, Linux Mint 17.2.
 
 
 Thanks for any clue.

This is normal behavior

http://www.cplusplus.com/reference/cstdio/feof/

"Notice that stream's internal position indicator may point to the
end-of-file for the next operation, but still, the end-of-file
indicator may not be set until an operation attempts to read at that
point."

crimaniak <crimaniak gmail.com> writes:

On Sunday, 20 September 2015 at 20:17:37 UTC, Dandyvica wrote:

 My file is made of 10 lines:


 cat numbers.txt
 1
 2
 3
 4
 5
 6
 7
 8
 9
 10

 ╰─$ wc -l numbers.txt

CR/LF can be interpreted as line _dividers_, so if you have CR or 
CR/LF at the end of line 10, really here is line 11 which is 
empty. Remove end of line symbols at line 10 and you will have 
expected output:

before readln eof=false, line=<1>, after readln eof=false
before readln eof=false, line=<2>, after readln eof=false
before readln eof=false, line=<3>, after readln eof=false
before readln eof=false, line=<4>, after readln eof=false
before readln eof=false, line=<5>, after readln eof=false
before readln eof=false, line=<6>, after readln eof=false
before readln eof=false, line=<7>, after readln eof=false
before readln eof=false, line=<8>, after readln eof=false
before readln eof=false, line=<9>, after readln eof=false
before readln eof=false, line=<10>, after readln eof=true

p.s. it's good style to check input parameters, even for most 
simple cases.