lsns

List system namespaces.

Scans /proc/*/ns/ to discover namespaces and aggregates process counts.

Implemented

• List all namespaces with type, process count, lowest PID, user, and command
• -J / --json: JSON output
• -r / --raw: raw output
• -n / --noheadings: suppress header
• -o / --output: select columns (NS, TYPE, NPROCS, PID, PPID, COMMAND, UID, USER)
• --output-all: show all columns
• -t / --type: filter by namespace type (mnt, net, ipc, user, pid, uts, cgroup, time)
• -p / --task: show namespaces for a specific PID
• Positional namespace inode filter

Not yet implemented

• -l / --list: list format (currently the default)
• -P / --persistent: show namespaces without processes
• -Q / --filter: display filter expressions
• -u / --notruncate: don’t truncate text
• -W / --nowrap: no multi-line representation
• -T / --tree: tree format (parent, owner, or process)
• NETNSID, NSFS, PNS, ONS columns