http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30162
--- Comment #43 from Dominique d'Humieres <dominiq at lps dot ens.fr>
2013-02-17 20:10:52 UTC ---
I finally had a look at this PR.
First the test on comment #41 works on x86_64-apple-darwin10 r196109:
macbook] f90/bug% mkfifo pipe
[macbook] f90/bug% read_f &
[1] 6998
[macbook] f90/bug% write_f
Hello, world!
[macbook] f90/bug%
[1] Done read_f
I have done the following changes to the original test:
[macbook] f90/bug% cat pr30162_1_db.f
integer status
integer i
open(unit=20,file='np',action='write',
& form='unformatted',iostat=status);
print*,'status for write from open is ',status
do i = 1,5
print *, "write ", i
write(20)i
end do
end
[macbook] f90/bug% cat pr30162_2_db.f
integer status
integer i
integer val
open(unit=21,file='np',action='read',
& form='unformatted',iostat=status);
print*,'status for read from open is ',status
do i = 1,5
read(21)val
print*,val
end do
end
and I got
[macbook] f90/bug% write_f
status for write from open is 0
write 1
At line 8 of file pr30162_1_db.f (unit = 20, file = 'np')
Fortran runtime error: Illegal seek
status for read from open is 0
At line 8 of file pr30162_2_db.f (unit = 21, file = 'np')
Fortran runtime error: I/O past end of record on unformatted file
[macbook] f90/bug%
[1] Exit 2 read_f
Then I have applied the following patch (based on r194679):
--- ../_clean/libgfortran/io/unix.c 2013-01-14 19:25:10.000000000 +0100
+++ libgfortran/io/unix.c 2013-02-17 20:23:43.000000000 +0100
@@ -336,7 +336,14 @@ raw_write (unix_stream * s, const void *
static gfc_offset
raw_seek (unix_stream * s, gfc_offset offset, int whence)
{
- return lseek (s->fd, offset, whence);
+ gfc_offset x;
+ x = lseek (s->fd, offset, whence);
+ /* Non-seekable files should always be assumed to be at
+ current position. */
+ if (x == -1 && errno == ESPIPE)
+ x = 0;
+ return x;
+ /* return lseek (s->fd, offset, whence); */
}
static gfc_offset
and now I get
[macbook] f90/bug% write_f
status for write from open is 0
write 1
write 2
write 3
write 4
write 5
status for read from open is 0
At line 8 of file pr30162_2_db.f (unit = 21, file = 'np')
Fortran runtime error: I/O past end of record on unformatted file
[macbook] f90/bug%
[1] Exit 2 read_f
So the write seems now OK. For the read, dtrace gives
fstat64(0x3, 0x7FFF5FBFD580, 0x50) = 0 0
fstat64(0x3, 0x7FFF5FBFD5C0, 0x0) = 0 0
lseek(0x3, 0x0, 0x1) = -1 Err#29
write(0x1, " status for read from open is 0\n\0", 0x2B) = 43
0
read(0x3, "\0", 0x4) = 4 0
read(0x3, "\0", 0x0) = 0 0
lseek(0x3, 0x4, 0x1) = -1 Err#29
write(0x2, "At line 8 of file pr30162_2_db.f (unit = 21, file = 'np')\n\0",
0x3A) = 58 0
write(0x2, "Fortran runtime error: \0", 0x17) = 23 0
write(0x2, "I/O past end of record on unformatted file\0", 0x2A) = 42 0
write(0x2, "\n\0", 0x1) = 1 0
close(0x3) = 0 0
i.e., 2 errors #29 on lseek. I did not find out how this is connected to the
error "I/O past end of record on unformatted file".
