trevor@trevbox:~$ cd linuxdir trevor@trevbox:~/linuxdir$ ls 1 file1 filerayson linfile mypip 2 file50505 files myfile mypipe file fileo filez myfiles pipe trevor@trevbox:~/linuxdir$ ls -la total 16 drwxrwxr-x 3 trevor trevor 4096 Jan 27 10:48 . drwxr-xr-x 17 trevor trevor 4096 Jan 27 10:45 .. -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:29 1 -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:29 2 -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:43 file -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:31 file1 -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:29 file50505 -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:48 fileo -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:29 filerayson prw-rw-r-- 1 trevor trevor 0 Jan 27 10:31 files -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:48 filez -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:31 linfile drwxrwxr-x 2 trevor trevor 4096 Jan 27 10:08 myfile -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:25 myfiles -rw-rw-r-- 1 trevor trevor 31 Jan 27 10:44 mypip prw-rw-r-- 1 trevor trevor 0 Jan 27 10:43 mypipe prw-rw-r-- 1 trevor trevor 0 Jan 27 10:18 pipe trevor@trevbox:~/linuxdir$ cat file trevor@trevbox:~/linuxdir$ more file trevor@trevbox:~/linuxdir$ less file trevor@trevbox:~/linuxdir$ ps aux | file Usage: file [-bcEhikLlNnprsvzZ0] [--apple] [--extension] [--mime-encoding] [--mime-type] [-e testname] [-F separator] [-f namefile] [-m magicfiles] file ... file -C [-m magicfiles] file [--help] trevor@trevbox:~/linuxdir$ ps aux | more USER PID %CPU %MEM VSZ RSS TTY STAT START TIM E COMMAND root 1 0.0 0.5 225108 8780 ? Ss 09:36 0:0 4 /sbin/init splash root 2 0.0 0.0 0 0 ? S 09:36 0:0 0 [kthreadd] root 3 0.0 0.0 0 0 ? I< 09:36 0:0 0 [rcu_gp] root 4 0.0 0.0 0 0 ? I< 09:36 0:0 0 [rcu_par_gp] root 6 0.0 0.0 0 0 ? I< 09:36 0:0 0 [kworker/0:0H-kb] root 9 0.0 0.0 0 0 ? I< 09:36 0:0 0 [mm_percpu_wq] root 10 0.0 0.0 0 0 ? S 09:36 0:0 0 [ksoftirqd/0] root 11 0.0 0.0 0 0 ? I 09:36 0:0 4 [rcu_sched] root 12 0.0 0.0 0 0 ? S 09:36 0:0 0 [migration/0] root 13 0.0 0.0 0 0 ? S 09:36 0:0 0 [idle_inject/0] trevor@trevbox:~/linuxdir$ file /bin/echo /bin/echo: ELF 64-bit LSB shared object, x86-64, version 1 (SYSV), dynamically linked, interpreter /lib64/ld-linux-x86-64.so.2, for GNU/Linux 3.2.0, BuildID[sha1]=057373f1356c861e0ec5b52c72804c86c6842cd5, stripped trevor@trevbox:~/linuxdir$ sudo apt-get update [sudo] password for trevor: Hit:1 http://us.archive.ubuntu.com/ubuntu bionic InRelease Get:2 http://security.ubuntu.com/ubuntu bionic-security InRelease [88.7 kB] Get:3 http://packages.elementary.io/appcenter bionic InRelease [5,909 B] Get:4 http://us.archive.ubuntu.com/ubuntu bionic-updates InRelease [88.7 kB] Hit:5 http://ppa.launchpad.net/elementary-os/stable/ubuntu bionic InRelease Get:6 http://us.archive.ubuntu.com/ubuntu bionic-backports InRelease [74.6 kB] Get:7 http://packages.elementary.io/appcenter bionic/main amd64 DEP-11 Metadata [292 kB] Get:8 http://security.ubuntu.com/ubuntu bionic-security/main amd64 DEP-11 Metadata [49.0 kB] Get:9 http://us.archive.ubuntu.com/ubuntu bionic-updates/main amd64 DEP-11 Metadata [294 kB] Get:10 http://security.ubuntu.com/ubuntu bionic-security/universe amd64 DEP-11 Metadata [59.8 kB] Get:11 http://security.ubuntu.com/ubuntu bionic-security/multiverse amd64 DEP-11 Metadata [2,464 B] Get:12 http://us.archive.ubuntu.com/ubuntu bionic-updates/universe amd64 DEP-11 Metadata [289 kB] Get:13 http://us.archive.ubuntu.com/ubuntu bionic-updates/multiverse amd64 DEP-11 Metadata [2,468 B] Get:14 http://us.archive.ubuntu.com/ubuntu bionic-backports/universe amd64 DEP-11 Metadata [9,288 B] Hit:15 http://ppa.launchpad.net/elementary-os/os-patches/ubuntu bionic InRelease Hit:16 http://ppa.launchpad.net/philip.scott/elementary-tweaks/ubuntu bionic InRelease Fetched 1,256 kB in 5s (269 kB/s) Reading package lists... Done trevor@trevbox:~/linuxdir$ string /bin/echo | echo Command 'string' not found, did you mean: command 'spring' from deb ruby-spring command 'spring' from deb spring command 'strings' from deb binutils Try: sudo apt install trevor@trevbox:~/linuxdir$ strings /bin/echo | less trevor@trevbox:~/linuxdir$ cd /etc trevor@trevbox:/etc$ ls -l | more total 1088 drwxr-xr-x 3 root root 4096 Aug 14 13:51 acpi -rw-r--r-- 1 root root 3028 Aug 14 13:46 adduser.conf -rw-r--r-- 1 root root 16 Jan 20 10:06 adjtime drwxr-xr-x 2 root root 4096 Jan 20 12:35 alternatives -rw-r--r-- 1 root root 401 May 29 2017 anacrontab drwxr-xr-x 4 root root 4096 Aug 14 13:50 apache2 drwxr-xr-x 6 root root 4096 Aug 14 13:49 apm drwxr-xr-x 3 root root 4096 Aug 14 13:51 apparmor drwxr-xr-x 8 root root 4096 Jan 20 10:53 apparmor.d drwxr-xr-x 5 root root 4096 Jan 20 10:53 apport -rw-r--r-- 1 root root 769 Mar 18 2020 appstream.conf drwxr-xr-x 7 root root 4096 Jan 20 12:30 apt drwxr-xr-x 3 root root 4096 Aug 14 13:53 avahi -rw-r--r-- 1 root root 2599 Jul 8 2019 bash.bashrc -rw-r--r-- 1 root root 45 Apr 1 2018 bash_completion drwxr-xr-x 2 root root 4096 Aug 14 13:57 bash_completion.d -rw-r--r-- 1 root root 8095 Jul 8 2019 bash_preexec -rw-r--r-- 1 root root 367 Jan 27 2016 bindresvport.black list drwxr-xr-x 2 root root 4096 Apr 20 2018 binfmt.d drwxr-xr-x 2 root root 4096 Aug 14 13:51 bluetooth trevor@trevbox:/etc$ cd /dev trevor@trevbox:/dev$ ls -l | more total 0 crw-r--r-- 1 root root 10, 235 Jan 27 2021 autofs drwxr-xr-x 2 root root 260 Jan 27 2021 block drwxr-xr-x 2 root root 80 Jan 27 2021 bsg crw-rw---- 1 root disk 10, 234 Jan 27 2021 btrfs-control drwxr-xr-x 3 root root 60 Jan 27 2021 bus lrwxrwxrwx 1 root root 3 Jan 27 2021 cdrom -> sr0 drwxr-xr-x 2 root root 3740 Jan 27 2021 char crw------- 1 root root 5, 1 Jan 27 2021 console lrwxrwxrwx 1 root root 11 Jan 27 2021 core -> /proc/ kcore crw------- 1 root root 10, 59 Jan 27 2021 cpu_dma_latenc y crw------- 1 root root 10, 203 Jan 27 2021 cuse drwxr-xr-x 6 root root 120 Jan 27 2021 disk drwxr-xr-x 3 root root 100 Jan 27 2021 dri lrwxrwxrwx 1 root root 3 Jan 27 2021 dvd -> sr0 crw------- 1 root root 10, 62 Jan 27 2021 ecryptfs crw-rw---- 1 root video 29, 0 Jan 27 2021 fb0 lrwxrwxrwx 1 root root 13 Jan 27 2021 fd -> /proc/se lf/fd crw-rw-rw- 1 root root 1, 7 Jan 27 2021 full crw-rw-rw- 1 root root 10, 229 Jan 27 2021 fuse crw------- 1 root root 241, 0 Jan 27 2021 hidraw0 crw------- 1 root root 10, 228 Jan 27 2021 hpet drwxr-xr-x 2 root root 0 Jan 27 2021 hugepages crw------- 1 root root 10, 183 Jan 27 2021 hwrng trevor@trevbox:/dev$ cd trevor@trevbox:~$ cd linuxdir trevor@trevbox:~/linuxdir$ ls 1 file1 filerayson linfile mypip 2 file50505 files myfile mypipe file fileo filez myfiles pipe trevor@trevbox:~/linuxdir$ mkfifo xyz trevor@trevbox:~/linuxdir$ ls -l total 8 -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:29 1 -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:29 2 -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:43 file -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:31 file1 -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:29 file50505 -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:48 fileo -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:29 filerayson prw-rw-r-- 1 trevor trevor 0 Jan 27 10:31 files -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:48 filez -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:31 linfile drwxrwxr-x 2 trevor trevor 4096 Jan 27 10:08 myfile -rw-rw-r-- 1 trevor trevor 0 Jan 27 10:25 myfiles -rw-rw-r-- 1 trevor trevor 31 Jan 27 10:44 mypip prw-rw-r-- 1 trevor trevor 0 Jan 27 10:43 mypipe prw-rw-r-- 1 trevor trevor 0 Jan 27 10:18 pipe prw-rw-r-- 1 trevor trevor 0 Jan 27 11:09 xyz trevor@trevbox:~/linuxdir$ cd ~/linuxdir trevor@trevbox:~/linuxdir$ touch hello trevor@trevbox:~/linuxdir$ touch file2 file3 file4 file5 trevor@trevbox:~/linuxdir$ touch file10 file12 file11 trevor@trevbox:~/linuxdir$ ls 1 file10 file3 fileo hello mypip 2 file11 file4 filerayson linfile mypipe file file12 file5 files myfile pipe file1 file2 file50505 filez myfiles xyz trevor@trevbox:~/linuxdir$ file files files: fifo (named pipe) trevor@trevbox:~/linuxdir$ file 1 1: empty trevor@trevbox:~/linuxdir$ ls 1 file10 file3 fileo hello mypip 2 file11 file4 filerayson linfile mypipe file file12 file5 files myfile pipe file1 file2 file50505 filez myfiles xyz trevor@trevbox:~/linuxdir$ ls file* file file10 file12 file3 file5 fileo files file1 file11 file2 file4 file50505 filerayson filez trevor@trevbox:~/linuxdir$ ls file? file1 file2 file3 file4 file5 fileo files filez trevor@trevbox:~/linuxdir$ ls file?? file10 file11 file12 trevor@trevbox:~/linuxdir$ ls file[0-9] file1 file2 file3 file4 file5 trevor@trevbox:~/linuxdir$ history | tail -20 324 cd /dev 325 ls -l | more 326 cd 327 cd linuxdir 328 ls 329 mkfifo xyz 330 ls -l 331 cd ~/linuxdir 332 touch hello 333 touch file2 file3 file4 file5 334 touch file10 file12 file11 335 ls 336 file files 337 file 1 338 ls 339 ls file* 340 ls file? 341 ls file?? 342 ls file[0-9] 343 history | tail -20 trevor@trevbox:~/linuxdir$ cd trevor@trevbox:~$ history | tail -50 296 ls file [0-9] 297 history | tail 20 298 cd 299 history |tail 20 300 history | tail -20 301 c 302 qwee 303 a 304 cat files > mypipe 305 cd linuxdir 306 cat files > mypipe 307 at files > mypipe 308 p 309