> Ian.
>
>> My environment and gcc version are like this:
>>
>> root@gavin-desktop:~# uname -a
>> Linux gavin-desktop 2.6.32-5-xen-amd64 #1 SMP Thu May 19 01:16:47 UTC
>> 2011 x86_64 GNU/Linux
>>
>> root@gavin-desktop:~# gcc -v
>> Using built-in specs.
>> Target: x86_64-linux-gnu
>> Configured with: ../src/configure -v --with-pkgversion='Ubuntu
>> 4.4.3-4ubuntu5'
>> --with-bugurl=file:///usr/share/doc/gcc-4.4/README.Bugs
>> --enable-languages=c,c++,fortran,objc,obj-c++ --prefix=/usr
>> --enable-shared --enable-multiarch --enable-linker-build-id
>> --with-system-zlib --libexecdir=/usr/lib --without-included-gettext
>> --enable-threads=posix --with-gxx-include-dir=/usr/include/c++/4.4
>> --program-suffix=-4.4 --enable-nls --enable-clocale=gnu
>> --enable-libstdcxx-debug --enable-plugin --enable-objc-gc
>> --disable-werror --with-arch-32=i486 --with-tune=generic
>> --enable-checking=release --build=x86_64-linux-gnu
>> --host=x86_64-linux-gnu --target=x86_64-linux-gnu
>> Thread model: posix
>> gcc version 4.4.3 (Ubuntu 4.4.3-4ubuntu5)
>>
>>
>>
>>
>> Thanks,
>> Bei Guan
>>
>>
>>
>>
>>
>> 8<------------------------------------------------------
>>
>> # HG changeset patch
>> # User Ian Campbell <
ian.campbell@xxxxxxxxxx>
>> # Date 1336751175 -3600
>> # Node ID 15ed8f45c4e57a1e206af020e0ff17b792108e99
>> # Parent adc74e492edfee6cf44e433e3e93743a3cf71999
>> blktap: avoid attribute warn_unused_result build failures.
>>
>> I'm not proud of this, but since none of these callers of
>> read/write have any
>> other error handling and return void themselves (for several
>> links up the call
>> chain AFAICT) and because I don't really want to get into a
>> massive reworking
>> of blktap2 I suppose it is at least pragmatic
>>
>> Signed-off-by: Ian Campbell <
ian.campbell@xxxxxxxxxx>
>>
>> diff -r adc74e492edf -r 15ed8f45c4e5
>> tools/blktap2/drivers/tapdisk-log.c
>> --- a/tools/blktap2/drivers/tapdisk-log.c Fri May 11
>> 16:19:16 2012 +0100
>> +++ b/tools/blktap2/drivers/tapdisk-log.c Fri May 11
>> 16:46:15 2012 +0100
>> @@ -247,7 +247,7 @@ tlog_flush(void)
>> wsize = ((size + 511) & (~511));
>>
>> memset(tapdisk_log.buf + size, '\n', wsize - size);
>> - write(fd, tapdisk_log.buf, wsize);
>> + (void)write(fd, tapdisk_log.buf, wsize);
>>
>> tapdisk_log.p = tapdisk_log.buf;
>>
>> diff -r adc74e492edf -r 15ed8f45c4e5
>> tools/blktap2/drivers/tapdisk-queue.c
>> --- a/tools/blktap2/drivers/tapdisk-queue.c Fri May 11
>> 16:19:16 2012 +0100
>> +++ b/tools/blktap2/drivers/tapdisk-queue.c Fri May 11
>> 16:46:15 2012 +0100
>> @@ -435,7 +435,7 @@ tapdisk_lio_ack_event(struct tqueue *que
>> uint64_t val;
>>
>> if (lio->flags & LIO_FLAG_EVENTFD)
>> - read(lio->event_fd, &val, sizeof(val));
>> + (void)read(lio->event_fd, &val, sizeof(val));
>> }
>>
>> static void
>> diff -r adc74e492edf -r 15ed8f45c4e5
>> tools/blktap2/drivers/tapdisk-stream.c
>> --- a/tools/blktap2/drivers/tapdisk-stream.c Fri May 11
>> 16:19:16 2012 +0100
>> +++ b/tools/blktap2/drivers/tapdisk-stream.c Fri May 11
>> 16:46:15 2012 +0100
>> @@ -145,7 +145,7 @@ tapdisk_stream_poll_clear(struct tapdisk
>> {
>> int dummy;
>>
>> - read(p->pipe[POLL_READ], &dummy, sizeof(dummy));
>> + (void)read(p->pipe[POLL_READ], &dummy, sizeof(dummy));
>> p->set = 0;
>> }
>>
>> @@ -155,7 +155,7 @@ tapdisk_stream_poll_set(struct tapdisk_s
>> int dummy = 0;
>>
>> if (!p->set) {
>> - write(p->pipe[POLL_WRITE], &dummy,
>> sizeof(dummy));
>> + (void)write(p->pipe[POLL_WRITE], &dummy,
>> sizeof(dummy));
>> p->set = 1;
>> }
>> }
>> @@ -203,7 +203,7 @@ tapdisk_stream_print_request(struct tapd
>> {
>> unsigned long idx = (unsigned
>> long)tapdisk_stream_request_idx(s, sreq);
>> char *buf = (char *)MMAP_VADDR(s->vbd->ring.vstart,
>> idx, 0);
>> - write(s->out_fd, buf, sreq->secs << SECTOR_SHIFT);
>> + (void)write(s->out_fd, buf, sreq->secs <<
>> SECTOR_SHIFT);
>> }
>>
>> static void
>> diff -r adc74e492edf -r 15ed8f45c4e5
>> tools/blktap2/drivers/tapdisk2.c
>> --- a/tools/blktap2/drivers/tapdisk2.c Fri May 11 16:19:16
>> 2012 +0100
>> +++ b/tools/blktap2/drivers/tapdisk2.c Fri May 11 16:46:15
>> 2012 +0100
>> @@ -79,7 +79,12 @@ main(int argc, char *argv[])
>> if (optind != argc)
>> usage(argv[0], EINVAL);
>>
>> - chdir("/");
>> + if (chdir("/")) {
>> + DPRINTF("failed to chdir(/): %d\n", errno);
>> + err = 1;
>> + goto out;
>> + }
>> +
>> tapdisk_start_logging("tapdisk2");
>>
>> err = tapdisk_server_init();
>>
>>
>>
>>
>>
>> --
>> Best Regards,
>> Bei Guan
>>
>
>
