stdout output missing, but redirecting works

stdout output missing, but redirecting works

[Brian Craft]

I compiled a program yesterday which output some lines to stdout. It
appeared to be working. Running it today, I get nothing on stdout.
However, if I redirect stdout to a file, the correct output appears in
the file. E.g.

# no output
./foo
# "hello world" in bar
./foo > bar


In between yesterday and today, I've rebooted and run rebaseall, so
perhaps one of those is responsible for the change.

Any suggestions?

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Re: stdout output missing, but redirecting works

[Larry Hall (Cygwin)]

On 12/9/2011 2:47 PM, Brian Craft wrote:
> I compiled a program yesterday which output some lines to stdout. It
> appeared to be working. Running it today, I get nothing on stdout.
> However, if I redirect stdout to a file, the correct output appears in
> the file. E.g.
>
> # no output
> ./foo
> # "hello world" in bar
> ./foo>  bar
>
>
> In between yesterday and today, I've rebooted and run rebaseall, so
> perhaps one of those is responsible for the change.
>
> Any suggestions?

Sounds like buffering to me.  Is this program compiled with Cygwin's gcc
or something else?  What kind of terminal are you running it in?  Same one
as yesterday?

-- 
Larry

_____________________________________________________________________

A: Yes.
 > Q: Are you sure?
 >> A: Because it reverses the logical flow of conversation.
 >>> Q: Why is top posting annoying in email?

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Re: stdout output missing, but redirecting works

[Brian Craft]

On Fri, Dec 9, 2011 at 12:44 PM, Larry Hall (Cygwin) wrote:
> On 12/9/2011 2:47 PM, Brian Craft wrote:
>>
>> I compiled a program yesterday which output some lines to stdout. It
>> appeared to be working. Running it today, I get nothing on stdout.
>> However, if I redirect stdout to a file, the correct output appears in
>> the file. E.g.
>>
>> # no output
>> ./foo
>> # "hello world" in bar
>> ./foo>  bar
>>
>>
>> In between yesterday and today, I've rebooted and run rebaseall, so
>> perhaps one of those is responsible for the change.
>>
>> Any suggestions?
>
>
> Sounds like buffering to me.  Is this program compiled with Cygwin's gcc
> or something else?  What kind of terminal are you running it in?  Same one
> as yesterday?

Cygwin's g++. The default cygwin terminal.

Another bit of data: if I explicitly redirect the output to /dev/tty0,
I also get no output. E.g.

# outputs "hello"
echo hello > /dev/tty0
# no output
./foo > /dev/tty0

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Re: stdout output missing, but redirecting works

[Larry Hall (Cygwin)]

On 12/9/2011 7:12 PM, Brian Craft wrote:
> On Fri, Dec 9, 2011 at 12:44 PM, Larry Hall (Cygwin) wrote:
>> On 12/9/2011 2:47 PM, Brian Craft wrote:
>>>
>>> I compiled a program yesterday which output some lines to stdout. It
>>> appeared to be working. Running it today, I get nothing on stdout.
>>> However, if I redirect stdout to a file, the correct output appears in
>>> the file. E.g.
>>>
>>> # no output
>>> ./foo
>>> # "hello world" in bar
>>> ./foo>    bar
>>>
>>>
>>> In between yesterday and today, I've rebooted and run rebaseall, so
>>> perhaps one of those is responsible for the change.
>>>
>>> Any suggestions?
>>
>>
>> Sounds like buffering to me.  Is this program compiled with Cygwin's gcc
>> or something else?  What kind of terminal are you running it in?  Same one
>> as yesterday?
>
> Cygwin's g++. The default cygwin terminal.
>
> Another bit of data: if I explicitly redirect the output to /dev/tty0,
> I also get no output. E.g.
>
> # outputs "hello"
> echo hello>  /dev/tty0
> # no output
> ./foo>  /dev/tty0

Then my next WAG is BLODA - <http://cygwin.com/acronyms/#BLODA>.  If that's
not it, I recommend a full report - <http://cygwin.com/problems.html>.

-- 
Larry

_____________________________________________________________________

A: Yes.
 > Q: Are you sure?
 >> A: Because it reverses the logical flow of conversation.
 >>> Q: Why is top posting annoying in email?

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