Re^17: Net::OpenSSH loosing lines ins reply

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Re^18: Net::OpenSSH loosing lines ins reply by Andy16 (Acolyte) on Jun 05, 2014 at 06:18 UTC
Good morning Salva, I think you lead us to the correct track... :-) `open OUT, ">", "./trace.out"; my $line =0; foreach (@cmdout) { $line++; my $bytes = print $line.": ".$_; print OUT "$line: bytes: $bytes, err: $! \n"; } close(OUT);` [download] IF everything is fine trace looks like this for all lines: `... 1880: bytes: 1, err: Inappropriate ioctl for device 1881: bytes: 1, err: Inappropriate ioctl for device 1882: bytes: 1, err: Inappropriate ioctl for device 1883: bytes: 1, err: Inappropriate ioctl for device 1884: bytes: 1, err: Inappropriate ioctl for device ...` [download] IF it starts to fail: `... 1891: bytes: 1, err: Inappropriate ioctl for device 1892: bytes: 1, err: Inappropriate ioctl for device 1893: bytes: , err: Resource temporarily unavailable 1894: bytes: , err: Resource temporarily unavailable 1895: bytes: , err: Resource temporarily unavailable 1896: bytes: , err: Resource temporarily unavailable 1897: bytes: , err: Resource temporarily unavailable ...` [download] Does this ring a bell? update caught it in strace: write(1, "07651738\n1313: switchport acce"..., 4096) = 4096 write(1, ": interface Ethernet2/36\n1426: "..., 4096) = 4096 write(1, "ntrusted\n1539: service-policy "..., 4096) = 4096 write(1, "torm-control broadcast level 10."..., 4096) = 4096 write(1, "rol broadcast level 10.00\n1782: "..., 4096) = -1 EAGAIN (Re +source temporarily unavailable) write(1, "t level 10.00\n1894: service-po"..., 4096) = -1 EAGAIN (Re +source temporarily unavailable) write(1, "e-policy type queuing input N7K-"..., 4096) = -1 EAGAIN (Res +ource temporarily unavailable) write(1, "141: channel-group 1305 mode a"..., 4096) = -1 EAGAIN (Res +ource temporarily unavailable) write(1, "storm-control broadcast level 10"..., 4096) = -1 EAGAIN (Res +ource temporarily unavailable) [download]	[reply] [d/l] [select]
Re^19: Net::OpenSSH loosing lines ins reply by salva (Canon) on Jun 05, 2014 at 08:55 UTC
`write(1, "torm-control broadcast level 10."..., 4096) = 4096 write(1, "rol broadcast level 10.00\n1782: "..., 4096) = -1 EAGAIN (Re +source temporarily unavailable)` [download] The only plausible explanation I can think of is OpenSSH `ssh` setting `STDOUT` into non-blocking mode. BTW, how are you capturing STDOUT? Add a dump of `/proc/$$/fdinfo`: `open OUT, ">", "./trace.out"; for (0, 1, 2) { local $/; open my $fdinfo, '<', "/proc/$$/fdinfo/$_"; my $info = <$fdinfo>; print OUT "fdinfo $_:\n$info\n\n"; } my $line =0; foreach (@cmdout) { $line++; my $bytes = print $line.": ".$_; print OUT "$line: bytes: $bytes, err: $! \n"; } close(OUT);` [download] The non-blocking flag is 0x4000. You may also like to generate dumps of `fdinfo` before the constructor call and before and after calling `capture`.	[reply] [d/l] [select]
Re^20: Net::OpenSSH loosing lines ins reply by Andy16 (Acolyte) on Jun 05, 2014 at 09:28 UTC
Hi Salva, on a normal run: `============================== start fdinfo 0: pos: 0 flags: 0100002 fdinfo 1: pos: 0 flags: 01 fdinfo 2: pos: 0 flags: 01 ============================== after new fdinfo 0: pos: 0 flags: 0100002 fdinfo 1: pos: 0 flags: 01 fdinfo 2: pos: 0 flags: 01 ============================== after capture fdinfo 0: pos: 0 flags: 0100002 fdinfo 1: pos: 0 flags: 04001 fdinfo 2: pos: 0 flags: 04001` [download] for a failed run: `============================== start fdinfo 0: pos: 0 flags: 0100002 fdinfo 1: pos: 0 flags: 01 fdinfo 2: pos: 0 flags: 01 ============================== after new fdinfo 0: pos: 0 flags: 0100002 fdinfo 1: pos: 0 flags: 01 fdinfo 2: pos: 0 flags: 01 ============================== after capture fdinfo 0: pos: 0 flags: 0100002 fdinfo 1: pos: 0 flags: 04001 fdinfo 2: pos: 0 flags: 04001` [download] so the same.... doesn't mean any thing to me... :-( I capture output using "tee" or even simpler only using "wc -l". For really using the script it would be called by another script and stdout would be read by caller.	[reply] [d/l] [select]
Re^21: Net::OpenSSH loosing lines ins reply by salva (Canon) on Jun 05, 2014 at 09:57 UTC
Re^22: Net::OpenSSH loosing lines ins reply by Andy16 (Acolyte) on Jun 05, 2014 at 10:45 UTC