[rcr] make File#dup intuitive

Simon_Strandgaard1 · 20 May 2004 16:22

position is not copied… try this example for yourself

f1 = File.open(FILE, ‘r’)
f1.seek(5)
p f1.pos # → 5
f2 = f1.dup
p f2.pos # → garbage

ruby a.rb
5
93

This is really non-intuitive that you have to do
a seek afterwards. Its the same as if you clone a string,
but have to copy the string-content yourself.
Where is logic here?

···

–
Simon Strandgaard

daz · 20 May 2004 22:13

Simon Strandgaard wrote:

position is not copied… try this example for yourself

f1 = File.open(FILE, ‘r’)
f1.seek(5)
p f1.pos # → 5
f2 = f1.dup
p f2.pos # → garbage

ruby a.rb
5
93

This is really non-intuitive that you have to do
a seek afterwards. Its the same as if you clone a string,
but have to copy the string-content yourself.
Where is logic here?

Works here.

ruby 1.9.0 (2004-04-27) [i586-bccwin32]

ruby 1.8.0 (2003-05-15) [i386-mswin32]

ruby 1.6.7 (2002-03-01) [i586-mswin32]

mainframe_19(north_garage)> ruby pos.rb
5
5
mainframe_19(north_garage)>

daz

Nobuyoshi_Nakada · 21 May 2004 06:25

Hi,

At Fri, 21 May 2004 01:22:49 +0900,
Simon Strandgaard wrote in [ruby-talk:100910]:

position is not copied… try this example for yourself

I’ve expected it had been fixed.

This patch works?

Index: io.c

···

===================================================================
RCS file: /cvs/ruby/src/ruby/io.c,v
retrieving revision 1.274
diff -U2 -p -d -r1.274 io.c
— io.c 8 May 2004 08:11:33 -0000 1.274
+++ io.c 21 May 2004 06:17:56 -0000
@@ -3295,4 +3295,5 @@ rb_io_init_copy(dest, io)
int fd;
char *mode;

off_t pos1, pos2;

io = rb_io_get_io(io);
@@ -3303,12 +3304,10 @@ rb_io_init_copy(dest, io)
if (orig->f2) {
io_fflush(orig->f2, orig);

fseeko(orig->f, 0L, SEEK_CUR);

pos2 = fseeko(orig->f2, 0L, SEEK_CUR);
}
else if (orig->mode & FMODE_WRITABLE) {
io_fflush(orig->f, orig);
}

else {
fseeko(orig->f, 0L, SEEK_CUR);
}

pos1 = fseeko(orig->f, 0L, SEEK_CUR);

/* copy OpenFile structure */
@@ -3332,4 +3331,5 @@ rb_io_init_copy(dest, io)
fd = ruby_dup(fileno(orig->f));
fptr->f = rb_fdopen(fd, mode);
fseeko(fptr->f, pos1, SEEK_SET);
if (orig->f2) {
if (fileno(orig->f) != fileno(orig->f2)) {
@@ -3337,4 +3337,5 @@ rb_io_init_copy(dest, io)
}
fptr->f2 = rb_fdopen(fd, “w”);
fseeko(fptr->f2, pos2, SEEK_SET);
}
if (fptr->mode & FMODE_BINMODE) {

–
Nobu Nakada

Simon_Strandgaard1 · 20 May 2004 22:19

daz wrote:

Simon Strandgaard wrote:

position is not copied… try this example for yourself

f1 = File.open(FILE, ‘r’)
f1.seek(5)
p f1.pos # → 5
f2 = f1.dup
p f2.pos # → garbage

ruby a.rb
5
93

This is really non-intuitive that you have to do
a seek afterwards. Its the same as if you clone a string,
but have to copy the string-content yourself.
Where is logic here?

Works here.

ruby 1.9.0 (2004-04-27) [i586-bccwin32]

ruby 1.8.0 (2003-05-15) [i386-mswin32]

ruby 1.6.7 (2002-03-01) [i586-mswin32]

mainframe_19(north_garage)> ruby pos.rb
5
5
mainframe_19(north_garage)>

Hmm… this begins to look like a freebsd specific problem.

ruby -v a.rb
ruby 1.9.0 (2004-05-17) [i386-freebsd5.1]
5
93
ruby18 -v a.rb
ruby 1.8.1 (2003-12-22) [i386-freebsd5.1]
5
93

···

–
Simon Strandgaard

Simon_Strandgaard1 · 21 May 2004 06:38

At Fri, 21 May 2004 01:22:49 +0900,
Simon Strandgaard wrote in [ruby-talk:100910]:

position is not copied… try this example for yourself

I’ve expected it had been fixed.

This patch works?

I just applied your patch… it seems as the position now
gets zeroed.

ruby a.rb
5
0
cat a.rb
f1 = File.open(FILE, ‘r’)
f1.seek(5)
p f1.pos # → 5
f2 = f1.dup
p f2.pos # → garbage

···

nobu.nokada@softhome.net wrote:

–
Simon Strandgaard

Nobuyoshi_Nakada · 21 May 2004 06:56

Hi,

At Fri, 21 May 2004 15:38:00 +0900,
Simon Strandgaard wrote in [ruby-talk:100979]:

I just applied your patch… it seems as the position now
gets zeroed.

Sorry, too stupid.

Index: io.c

···

===================================================================
RCS file: /cvs/ruby/src/ruby/io.c,v
retrieving revision 1.274
diff -u -2 -p -r1.274 io.c
— io.c 8 May 2004 08:11:33 -0000 1.274
+++ io.c 21 May 2004 06:55:56 -0000
@@ -3332,4 +3332,5 @@ rb_io_init_copy(dest, io)
fd = ruby_dup(fileno(orig->f));
fptr->f = rb_fdopen(fd, mode);

fseeko(fptr->f, ftello(orig->f), SEEK_SET);
if (orig->f2) {
if (fileno(orig->f) != fileno(orig->f2)) {
@@ -3337,4 +3338,5 @@ rb_io_init_copy(dest, io)
}
fptr->f2 = rb_fdopen(fd, “w”);
fseeko(fptr->f2, ftello(orig->f2), SEEK_SET);
}
if (fptr->mode & FMODE_BINMODE) {

–
Nobu Nakada

Simon_Strandgaard1 · 21 May 2004 07:00

At Fri, 21 May 2004 15:38:00 +0900,
Simon Strandgaard wrote in [ruby-talk:100979]:

I just applied your patch… it seems as the position now
gets zeroed.

Sorry, too stupid.

I have sligthly adjusted your original patch, so it now works

diff -U2 bak/io.c io.c
— bak/io.c Fri May 21 08:51:22 2004
+++ io.c Fri May 21 08:46:00 2004
@@ -3295,4 +3295,5 @@
int fd;
char *mode;

off_t pos1, pos2;

io = rb_io_get_io(io);
@@ -3303,12 +3304,11 @@
if (orig->f2) {
io_fflush(orig->f2, orig);

```
  fseeko(orig->f, 0L, SEEK_CUR);
```

```
  pos2 = fseeko(orig->f2, 0L, SEEK_CUR);
```
}
else if (orig->mode & FMODE_WRITABLE) {
io_fflush(orig->f, orig);
}

else {
```
  fseeko(orig->f, 0L, SEEK_CUR);
```
}

pos1 = io_tell(orig);
fseeko(orig->f, 0L, SEEK_CUR);

/* copy OpenFile structure */
@@ -3332,4 +3332,5 @@
fd = ruby_dup(fileno(orig->f));
fptr->f = rb_fdopen(fd, mode);
fseeko(fptr->f, pos1, SEEK_SET);
if (orig->f2) {
if (fileno(orig->f) != fileno(orig->f2)) {
@@ -3337,4 +3338,5 @@
}
fptr->f2 = rb_fdopen(fd, “w”);
```
  fseeko(fptr->f2, pos2, SEEK_SET);
```
}
if (fptr->mode & FMODE_BINMODE) {

I will try your patch right away. Thanks

···

nobu.nokada@softhome.net wrote:

–
Simon Strandgaard

Simon_Strandgaard1 · 21 May 2004 16:02

Simon Strandgaard wrote:

f1 = File.open(FILE, ‘r’)
f1.seek(5)
p f1.pos # → 5
f2 = f1.dup
p f2.pos # → garbage

ruby a.rb
5
93

Index: io.c

RCS file: /cvs/ruby/src/ruby/io.c,v
retrieving revision 1.274
diff -u -2 -p -r1.274 io.c
— io.c 8 May 2004 08:11:33 -0000 1.274
+++ io.c 21 May 2004 06:55:56 -0000
@@ -3332,4 +3332,5 @@ rb_io_init_copy(dest, io)
fd = ruby_dup(fileno(orig->f));
fptr->f = rb_fdopen(fd, mode);

fseeko(fptr->f, ftello(orig->f), SEEK_SET);
if (orig->f2) {
if (fileno(orig->f) != fileno(orig->f2)) {
@@ -3337,4 +3338,5 @@ rb_io_init_copy(dest, io)
}
fptr->f2 = rb_fdopen(fd, “w”);

fseeko(fptr->f2, ftello(orig->f2), SEEK_SET);
}
if (fptr->mode & FMODE_BINMODE) {

then Simon Strandgaard wrote:

Your new patch works like a charm

./ruby a.rb
5
5

Will this wonderful patch be committed to cvs ?

···

then nobu.nokada@softhome.net wrote:

–
Simon Strandgaard

Simon_Strandgaard1 · 21 May 2004 07:04

Simon Strandgaard wrote:

At Fri, 21 May 2004 15:38:00 +0900,
Simon Strandgaard wrote in [ruby-talk:100979]:

I just applied your patch… it seems as the position now
gets zeroed.

Sorry, too stupid.

I will try your patch right away. Thanks

Your new patch works like a charm

./ruby a.rb
5
5

···

nobu.nokada@softhome.net wrote:

–
Simon Strandgaard

Simon_Strandgaard1 · 25 May 2004 17:07

Simon Strandgaard wrote:

f1 = File.open(FILE, ‘r’)
f1.seek(5)
p f1.pos # → 5
f2 = f1.dup
p f2.pos # → garbage

ruby a.rb
5
93

[snip patch]

Will this wonderful patch be committed to cvs ?

Please allow Nobu to commit this patch… soon

···

then nobu.nokada@softhome.net wrote:

–
Simon Strandgaard

Yukihiro_Matsumoto2 · 26 May 2004 02:58

Hi,

···

In message “Re: [rcr] make File#dup intuitive” on 04/05/26, Simon Strandgaard neoneye@adslhome.dk writes:

Will this wonderful patch be committed to cvs ?

Please allow Nobu to commit this patch… soon

Go head, Nobu.

						matz.

Simon_Strandgaard1 · 26 May 2004 08:17

matz@ruby-lang.org (Yukihiro Matsumoto) wrote:

···

In message “Re: [rcr] make File#dup intuitive” > on 04/05/26, Simon Strandgaard neoneye@adslhome.dk writes:

Will this wonderful patch be committed to cvs ?

Please allow Nobu to commit this patch… soon

Go head, Nobu.

Excelent! a pleasant birthday present… Thanks Nobu+Matz.

–
Simon Strandgaard

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[rcr] make File#dup intuitive

ruby 1.9.0 (2004-04-27) [i586-bccwin32]

ruby 1.8.0 (2003-05-15) [i386-mswin32]

ruby 1.6.7 (2002-03-01) [i586-mswin32]

ruby 1.9.0 (2004-04-27) [i586-bccwin32]

ruby 1.8.0 (2003-05-15) [i386-mswin32]

ruby 1.6.7 (2002-03-01) [i586-mswin32]

Index: io.c

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