我所得到的内容的一个很好的例子：
尝试
ss -axl显示正在监听的 UNIX 域套接字。例如，这可能给出：Netid State Recv-Q Send-Q Local Address:Port Peer Address:Port u_str LISTEN 0 0 /run/systemd/private 9683 * 0 u_str LISTEN 0 0 /run/systemd/fsck.progress 9690 * 0 u_str LISTEN 0 0 /run/systemd/journal/stdout 9705 * 0 u_str LISTEN 0 0 /var/run/dbus/system_bus_socket 13830 * 0 u_str LISTEN 0 0 /run/thd.socket 13833 * 0 u_str LISTEN 0 0 /var/run/docker.sock 13835 * 0 u_str LISTEN 0 0 /run/avahi-daemon/socket 13837 * 0 u_str LISTEN 0 0 /run/user/1000/systemd/private 16088 * 0 u_str LISTEN 0 0 /run/user/1000/gnupg/S.dirmngr 16093 * 0 u_str LISTEN 0 0 /run/user/1000/gnupg/S.gpg-agent.extra 16094 * 0 u_str LISTEN 0 0 /run/user/1000/gnupg/S.gpg-agent.ssh 16095 * 0 u_str LISTEN 0 0 /run/user/1000/gnupg/S.gpg-agent 16096 * 0 u_str LISTEN 0 0 /run/user/1000/bus 16097 * 0 u_str LISTEN 0 0 /run/user/1000/gnupg/S.gpg-agent.browser 16098 * 0 u_str LISTEN 0 0 /var/run/dhcpcd.sock 16530 * 0 u_str LISTEN 0 0 /var/run/dhcpcd.unpriv.sock 16531 * 0 u_str LISTEN 0 0 /run/user/1000/vscode-git-363c8837e0.sock 2244296 * 0 u_str LISTEN 0 0 /run/user/1000/vscode-ipc-774023f9-edb0-4abd-8647-17c77c55a895.sock 2245117 * 0 u_str LISTEN 0 0 /run/user/1000/vscode-ipc-8d96b721-cae4-439d-a861-309d7c184d10.sock 2344995 * 0 u_str LISTEN 0 0 /run/user/1000/vscode-git-363c8837e0.sock 2244296 * 0 u_str LISTEN 0 0 /run/user/1000/vscode-ipc-774023f9-edb0-4abd-8647-17c77c55a895.sock 2245117 * 0 u_str LISTEN 0 0 /run/user/1000/vscode-ipc-8d96b721-cae4-439d-a861-309d7c184d10.sock 2344995 * 0现在用:过滤列表
grep：ss -axl | grep systemdu_str LISTEN 0 0 /run/systemd/private 9683 * 0 u_str LISTEN 0 0 /run/systemd/fsck.progress 9690 * 0 u_str LISTEN 0 0 /run/systemd/journal/stdout 9705 * 0 u_str LISTEN 0 0 /run/user/1000/systemd/private 16088 * 0
这些列仍然非常宽，无法在普通终端上很好地显示。
期望的结果是折叠列以适合通过过滤器的数据。可能ss有一种按路径过滤的方法（我还没有找到），但这ss只是一个示例，因此对于本练习，假设无法让应用程序过滤其输出并重新对齐列本身。
所需的输出可能如下所示：
u_str LISTEN 0 0 /run/systemd/private 9683 * 0
u_str LISTEN 0 0 /run/systemd/fsck.progress 9690 * 0
u_str LISTEN 0 0 /run/systemd/journal/stdout 9705 * 0
u_str LISTEN 0 0 /run/user/1000/systemd/private 16088 * 0
另一个可以看到这一点的情况是在df使用 ZFS 和 Docker 的系统列表中：
Filesystem 1K-blocks Used Available Use% Mounted on
devtmpfs 10240 0 10240 0% /dev
shm 8131012 0 8131012 0% /dev/shm
rpool/ROOT 923596 820504 86708 91% /
tmpfs 1626204 1900 1624304 1% /run
/dev/sdb1 65390 33432 31958 52% /boot
dockerpool/backup 57010048 4346880 52663168 8% /backup
dockerpool/docker 52723200 60032 52663168 1% /var/lib/docker
cgroup_root 10240 0 10240 0% /sys/fs/cgroup
dockerpool/docker/fa4cd75b75e1e4eca9cb94124c61529e98313cffa2960bd5adc55e7fe65717a1 52826624 163456 52663168 1% /var/lib/docker/zfs/graph/fa4cd75b75e1e4eca9cb94124c61529e98313cffa2960bd5adc55e7fe65717a1
dockerpool/docker/bf861c5d067c605bded3fe38794d0d291ec602b779a2eda9a46ba5ea472fc9a1 52826624 163456 52663168 1% /var/lib/docker/zfs/graph/bf861c5d067c605bded3fe38794d0d291ec602b779a2eda9a46ba5ea472fc9a1
dockerpool/docker/c9fe2509b8e5e335fcf0f2472abea90180cb443391d86db7dd0c6a4806e63180 52830976 167808 52663168 1% /var/lib/docker/zfs/graph/c9fe2509b8e5e335fcf0f2472abea90180cb443391d86db7dd0c6a4806e63180
dockerpool/docker/1edf9ca3849374d12ba3e9b6e5e72e8e844bc96de7c14e8e0045356b29bb2c4f 52823808 160640 52663168 1% /var/lib/docker/zfs/graph/1edf9ca3849374d12ba3e9b6e5e72e8e844bc96de7c14e8e0045356b29bb2c4f
dockerpool/docker/8d62982afac1d3840a5987a62e9e369d5ae29d27dcb0007d0d5319ad84b2c57c 52826624 163456 52663168 1% /var/lib/docker/zfs/graph/8d62982afac1d3840a5987a62e9e369d5ae29d27dcb0007d0d5319ad84b2c57c
dockerpool/docker/0f03f5e4ca7b9ba366643354c37ca1746a3009e97c1b9f1b0bea126a5eab5dc7 52708224 45056 52663168 1% /var/lib/docker/zfs/graph/0f03f5e4ca7b9ba366643354c37ca1746a3009e97c1b9f1b0bea126a5eab5dc7
shm 65536 0 65536 0% /var/lib/docker/containers/d8413602c199ff17c1324d2e166b1bff3c1115406f2f14475dbd54b7c938631a/mounts/shm
shm 65536 0 65536 0% /var/lib/docker/containers/d0f705e3be016b8b10522329c6f3e1c01d83fabc3d9a498bcfadc754a56fd3fe/mounts/shm
shm 65536 0 65536 0% /var/lib/docker/containers/15dbaf4a13d8136b415fe257e6790b4692f3aa2d0b0197ef7d1c0e90dec703da/mounts/shm
shm 65536 0 65536 0% /var/lib/docker/containers/b0f3856ab0ba0021832519448636498228f5b1ffedc57eec203283d514ec19ac/mounts/shm
shm 65536 0 65536 0% /var/lib/docker/containers/68c2691f0eebcf2f765bb4bfe00c4fdba749e36966e5b42afe8f9f63aeba5803/mounts/shm
shm 65536 0 65536 0% /var/lib/docker/containers/21431e15bc044019c517b4d14efbbf3eb3ce1078c4419c0adb924aaebf62e283/mounts/shm
dockerpool/docker/0dbc7d708e28e3e29b6360db440d3550ee414791e491b2d807b34079152d1487 52732416 69248 52663168 1% /var/lib/docker/zfs/graph/0dbc7d708e28e3e29b6360db440d3550ee414791e491b2d807b34079152d1487
dockerpool/docker/3df99a7e3ec5486160e1d55479931ea597f53c0ae021f422a5d11ccd7114917b 52674176 11008 52663168 1% /var/lib/docker/zfs/graph/3df99a7e3ec5486160e1d55479931ea597f53c0ae021f422a5d11ccd7114917b
dockerpool/docker/0f1380fdca3c53835ab637f378d11d0f81e1c8319aa59f6b289429223a48b4ed 53164928 501760 52663168 1% /var/lib/docker/zfs/graph/0f1380fdca3c53835ab637f378d11d0f81e1c8319aa59f6b289429223a48b4ed
dockerpool/docker/711415dbd6df49794b0a3b4066b274f5d752ed2a8e1ea2dcc5bdbfe57757380e 53001088 337920 52663168 1% /var/lib/docker/zfs/graph/711415dbd6df49794b0a3b4066b274f5d752ed2a8e1ea2dcc5bdbfe57757380e
dockerpool/docker/359ed871b4929d13789ab1f89bc9a170819ca1b1dfcb660f9ca2f60f0ac59d00 52826368 163200 52663168 1% /var/lib/docker/zfs/graph/359ed871b4929d13789ab1f89bc9a170819ca1b1dfcb660f9ca2f60f0ac59d00
dockerpool/docker/0009ba1b93a2e49bcf00d64b3c6a1df6b9d2e8d669b61732279100725f867043 53009408 346240 52663168 1% /var/lib/docker/zfs/graph/0009ba1b93a2e49bcf00d64b3c6a1df6b9d2e8d669b61732279100725f867043
dockerpool/docker/a1f1a7f4879e937bae9b9aeabea13cb5b291b02e133ff0c4d09f531c4e8fd04f 52717184 54016 52663168 1% /var/lib/docker/zfs/graph/a1f1a7f4879e937bae9b9aeabea13cb5b291b02e133ff0c4d09f531c4e8fd04f
dockerpool/docker/dc632a8bf6b8da1c5c06c7e2504508b8a024af10b58837afa7b6b4a468c2695f 53693824 1030656 52663168 2% /var/lib/docker/zfs/graph/dc632a8bf6b8da1c5c06c7e2504508b8a024af10b58837afa7b6b4a468c2695f
dockerpool/docker/a5ffc4c6e1076cc8104aae76997fa479e0d8a3cc437fc1c948177d8c2345cb2a 52903936 240768 52663168 1% /var/lib/docker/zfs/graph/a5ffc4c6e1076cc8104aae76997fa479e0d8a3cc437fc1c948177d8c2345cb2a
dockerpool/docker/8589313f7779178dcf776756e71d8623c4f8646ba766e92ce8e6dde074cc266a 53190912 527744 52663168 1% /var/lib/docker/zfs/graph/8589313f7779178dcf776756e71d8623c4f8646ba766e92ce8e6dde074cc266a
dockerpool/docker/243285ef997322c83565c47e6ff0d38bde8d35337ab767489cdc6a2d0735cae2 52907264 244096 52663168 1% /var/lib/docker/zfs/graph/243285ef997322c83565c47e6ff0d38bde8d35337ab767489cdc6a2d0735cae2
使用grep来过滤（我们不能只排除zfs文件系统，因为根文件系统也在 ZFS 上，所以我们只想排除 下的文件系统dockerpool）：
$ df | grep -v docker
Filesystem 1K-blocks Used Available Use% Mounted on
devtmpfs 10240 0 10240 0% /dev
shm 8131012 0 8131012 0% /dev/shm
rpool/ROOT 923596 820504 86708 91% /
tmpfs 1626204 1900 1624304 1% /run
/dev/sdb1 65390 33432 31958 52% /boot
cgroup_root 10240 0 10240 0% /sys/fs/cgroup
所需的输出看起来更像是：
Filesystem 1K-blocks Used Available Use% Mounted on
devtmpfs 10240 0 10240 0% /dev
shm 8131012 0 8131012 0% /dev/shm
rpool/ROOT 923596 820504 86708 91% /
tmpfs 1626204 1900 1624304 1% /run
/dev/sdb1 65390 33432 31958 52% /boot
cgroup_root 10240 0 10240 0% /sys/fs/cgroup
答案1
一个简单可行的解决方案是将数据传递给column -t.这将根据数据中的空白字符（制表符和空格）对齐列。
你的第一个输出：
$ column -t file1
u_str LISTEN 0 0 /run/systemd/private 9683 * 0
u_str LISTEN 0 0 /run/systemd/fsck.progress 9690 * 0
u_str LISTEN 0 0 /run/systemd/journal/stdout 9705 * 0
u_str LISTEN 0 0 /run/user/1000/systemd/private 16088 * 0
我想说这看起来不错。
你的第二个输出：
$ column -t file2
Filesystem 1K-blocks Used Available Use% Mounted on
devtmpfs 10240 0 10240 0% /dev
shm 8131012 0 8131012 0% /dev/shm
rpool/ROOT 923596 820504 86708 91% /
tmpfs 1626204 1900 1624304 1% /run
/dev/sdb1 65390 33432 31958 52% /boot
cgroup_root 10240 0 10240 0% /sys/fs/cgroup
注意到这个词是如何on获得一个单独的列的吗？这是由于字符串中的空格造成的Mounted on。对于这个特定案例来说，这可能不是一个大问题，但您应该意识到任何空格或制表符将被视为列分隔符。
如果您知道数据使用什么分隔符，则可以column通过其-s选项指定该分隔符，例如-s $'\t'inbash或zshto use only tabs。