Public bug reported: dumpcap -g is supposed to have the output file created with group read permission. It works only when specifying an output file with "-w".
Works (with -w): $ sudo -u root -g $(id -ng) /usr/bin/dumpcap -g -i enp0s25 -p -w /tmp/foo.pcapng [sudo] password for sdeziel: Capturing on 'enp0s25' File: /tmp/foo.pcapng Packets captured: 4 Packets received/dropped on interface 'enp0s25': 4/0 (pcap:0/dumpcap:0/flushed:0/ps_ifdrop:0) (100.0%) $ ll /tmp/foo.pcapng -rw-r----- 1 root sdeziel 1416 Jul 11 12:08 /tmp/foo.pcapng Does not work (without -w): $ sudo -u root -g $(id -ng) /usr/bin/dumpcap -g -i enp0s25 -p Capturing on 'enp0s25' File: /tmp/wireshark_enp0s25_20180711120842_0KgkEu.pcapng Packets captured: 37 Packets received/dropped on interface 'enp0s25': 37/0 (pcap:0/dumpcap:0/flushed:0/ps_ifdrop:0) (100.0%) $ ll /tmp/wireshark_enp0s25_20180711120842_0KgkEu.pcapng -rw------- 1 root sdeziel 5568 Jul 11 12:08 /tmp/wireshark_enp0s25_20180711120842_0KgkEu.pcapng ProblemType: Bug DistroRelease: Ubuntu 18.04 Package: wireshark-common 2.4.5-1 ProcVersionSignature: Ubuntu 4.15.0-24.26-generic 4.15.18 Uname: Linux 4.15.0-24-generic x86_64 NonfreeKernelModules: zfs zunicode zavl icp zcommon znvpair ApportVersion: 2.20.9-0ubuntu7.2 Architecture: amd64 CurrentDesktop: ubuntu:GNOME Date: Wed Jul 11 11:42:03 2018 InstallationDate: Installed on 2018-06-24 (16 days ago) InstallationMedia: Ubuntu 18.04 LTS "Bionic Beaver" - Release amd64 (20180622) ProcEnviron: TERM=xterm-256color PATH=(custom, no user) XDG_RUNTIME_DIR=<set> LANG=en_CA.UTF-8 SHELL=/bin/bash SourcePackage: wireshark UpgradeStatus: No upgrade log present (probably fresh install) ** Affects: wireshark (Ubuntu) Importance: Undecided Status: New ** Tags: amd64 apport-bug bionic third-party-packages -- You received this bug notification because you are a member of Ubuntu Bugs, which is subscribed to Ubuntu. https://bugs.launchpad.net/bugs/1781253 Title: dumpcap group read (-g) doesn't work without specifying an output file (-w) To manage notifications about this bug go to: https://bugs.launchpad.net/ubuntu/+source/wireshark/+bug/1781253/+subscriptions -- ubuntu-bugs mailing list ubuntu-bugs@lists.ubuntu.com https://lists.ubuntu.com/mailman/listinfo/ubuntu-bugs