R devel - Dec 2019 - Error in close.connection(p) : ignoring SIGPIPE signal

Not sure if this is a bug, so posting here first. If I run:

 ?? cnt <- 0L
 ?? while (TRUE) {
 ? ? ?? cnt <- cnt + 1L
 ? ? ?? p <- pipe("echo /dev/stdin > /dev/null", open =
"w")
 ? ? ?? writeLines("foobar", p)
 ? ? ?? tryCatch(close(p), error = function(e) { print(cnt); stop(e)})
 ?? }

then once cnt gets to around 650, it fails with:

 ?? [1] 654
 ?? Error in close.connection(p) : ignoring SIGPIPE signal

Should I not be using pipe() in this way? Here is my sessionInfo()

 ?? R version 3.6.0 (2019-04-26)
 ?? Platform: x86_64-pc-linux-gnu (64-bit)
 ?? Running under: Ubuntu 18.04.3 LTS

 ?? Matrix products: default
 ?? BLAS:?? /home/btyner/R360/lib64/R/lib/libRblas.so
 ?? LAPACK: /home/btyner/R360/lib64/R/lib/libRlapack.so

 ?? locale:
 ? ? [1] LC_CTYPE=en_US.UTF-8?????? LC_NUMERIC=C
 ? ? [3] LC_TIME=en_US.UTF-8??????? LC_COLLATE=en_US.UTF-8
 ? ? [5] LC_MONETARY=en_US.UTF-8??? LC_MESSAGES=en_US.UTF-8
 ? ? [7] LC_PAPER=en_US.UTF-8?????? LC_NAME=C
 ? ? [9] LC_ADDRESS=C?????????????? LC_TELEPHONE=C
 ?? [11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C

 ?? attached base packages:
 ?? [1] stats???? graphics? grDevices utils???? datasets? methods base

 ?? loaded via a namespace (and not attached):
 ?? [1] compiler_3.6.0

Regards,
Ben

Hi Benjamin,

you cannot pipe to echo, since it does not read from stdin. 

echo just echos is first arg, i.e. echo /dev/stdin > /dev/null will echo the
string "/dev/stdin"to /dev/stdout, which is redirected to /dev/null.

Try 

p <- pipe("cat > /dev/null", open = "w")

instead.

Regards,
Andreas

2019-12-06 02:46 GMT+01:00 Benjamin Tyner<btyner at
gmail.com>:
> Not sure if this is a bug, so posting here first. If I run:
> ?? cnt <- 0L
> ?? while (TRUE) {
> ? ? ?? cnt <- cnt + 1L
> ? ? ?? p <- pipe("echo /dev/stdin > /dev/null", open =
"w")
> ? ? ?? writeLines("foobar", p)
> ? ? ?? tryCatch(close(p), error = function(e) { print(cnt); stop(e)})
> ?? }
> 
> then once cnt gets to around 650, it fails with:
> 
> ?? [1] 654
> ?? Error in close.connection(p) : ignoring SIGPIPE signal
> 
> Should I not be using pipe() in this way? Here is my sessionInfo()
> 
> ?? R version 3.6.0 (2019-04-26)
> ?? Platform: x86_64-pc-linux-gnu (64-bit)
> ?? Running under: Ubuntu 18.04.3 LTS
> 
> ?? Matrix products: default
> ?? BLAS:?? /home/btyner/R360/lib64/R/lib/libRblas.so
> ?? LAPACK: /home/btyner/R360/lib64/R/lib/libRlapack.so
> 
> ?? locale:
> ? ? [1] LC_CTYPE=en_US.UTF-8?????? LC_NUMERIC=C
> ? ? [3] LC_TIME=en_US.UTF-8??????? LC_COLLATE=en_US.UTF-8
> ? ? [5] LC_MONETARY=en_US.UTF-8??? LC_MESSAGES=en_US.UTF-8
> ? ? [7] LC_PAPER=en_US.UTF-8?????? LC_NAME=C
> ? ? [9] LC_ADDRESS=C?????????????? LC_TELEPHONE=C
> ?? [11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C
> 
> ?? attached base packages:
> ?? [1] stats???? graphics? grDevices utils???? datasets? methods base
> 
> ?? loaded via a namespace (and not attached):
> ?? [1] compiler_3.6.0
> 
> Regards,
> Ben
> 
> ______________________________________________
> R-devel at r-project.org mailing list
> https://stat.ethz.ch/mailman/listinfo/r-devel
>

Andreas,

How right you are! Still, I find it curious that in the context of the 
while(TRUE) loop, I am allowed to do this 653 times, with failure on the 
654th attempt. Perhaps there is something asynchronous going on? If I 
eliminate the looping, it does indeed fail (as expected) on the first 
attempt to close the pipe.

Regards

Ben

On 12/6/19 2:04 AM, Andreas Kersting wrote:
> Hi Benjamin,
>
> you cannot pipe to echo, since it does not read from stdin.
>
> echo just echos is first arg, i.e. echo /dev/stdin > /dev/null will echo
the string "/dev/stdin"to /dev/stdout, which is redirected to
/dev/null.
>
> Try
>
> p <- pipe("cat > /dev/null", open = "w")
>
> instead.
>
> Regards,
> Andreas
>
> 2019-12-06 02:46 GMT+01:00 Benjamin Tyner<btyner at gmail.com>:
>> Not sure if this is a bug, so posting here first. If I run:
>>  ?? cnt <- 0L
>>  ?? while (TRUE) {
>>  ? ? ?? cnt <- cnt + 1L
>>  ? ? ?? p <- pipe("echo /dev/stdin > /dev/null", open =
"w")
>>  ? ? ?? writeLines("foobar", p)
>>  ? ? ?? tryCatch(close(p), error = function(e) { print(cnt); stop(e)})
>>  ?? }
>>
>> then once cnt gets to around 650, it fails with:
>>
>>  ?? [1] 654
>>  ?? Error in close.connection(p) : ignoring SIGPIPE signal
>>
>> Should I not be using pipe() in this way? Here is my sessionInfo()
>>
>>  ?? R version 3.6.0 (2019-04-26)
>>  ?? Platform: x86_64-pc-linux-gnu (64-bit)
>>  ?? Running under: Ubuntu 18.04.3 LTS
>>
>>  ?? Matrix products: default
>>  ?? BLAS:?? /home/btyner/R360/lib64/R/lib/libRblas.so
>>  ?? LAPACK: /home/btyner/R360/lib64/R/lib/libRlapack.so
>>
>>  ?? locale:
>>  ? ? [1] LC_CTYPE=en_US.UTF-8?????? LC_NUMERIC=C
>>  ? ? [3] LC_TIME=en_US.UTF-8??????? LC_COLLATE=en_US.UTF-8
>>  ? ? [5] LC_MONETARY=en_US.UTF-8??? LC_MESSAGES=en_US.UTF-8
>>  ? ? [7] LC_PAPER=en_US.UTF-8?????? LC_NAME=C
>>  ? ? [9] LC_ADDRESS=C?????????????? LC_TELEPHONE=C
>>  ?? [11] LC_MEASUREMENT=en_US.UTF-8 LC_IDENTIFICATION=C
>>
>>  ?? attached base packages:
>>  ?? [1] stats???? graphics? grDevices utils???? datasets? methods base
>>
>>  ?? loaded via a namespace (and not attached):
>>  ?? [1] compiler_3.6.0
>>
>> Regards,
>> Ben
>>
>> ______________________________________________
>> R-devel at r-project.org mailing list
>> https://stat.ethz.ch/mailman/listinfo/r-devel