Unix Vs Powershell Commands: a Comparison (Under Development)

Unix vs PowerShell Commands: A Comparison (Under Development)

Unix Powershell/Cmd Description

/dev/null out-null Instead of a pseudo-device, output can be directed to a command: do- something | out-null. To redirect other streams use: do-something 2>$null bash command, cmd, powershell create a subshell cat get-content output a file to stdout aliases: cat, gc, type cd set-location change directory aliases: sl, cd, chdir chmod See set-acl change file permissions attrib Windows handles file permissions very set-itemproperty differently cp Copy-item Copy a file or a directory curl invoke-webRequest -uri file retrieve a file using http alias: curl cut Select-Object Extract columns from output (not quite the same date get-date Display a date, extracting fields df get-disk Show free storage on the disk du Show disk utilization echo echo output a string, variables exit exit Exit a script or a subshell with an error code env get-childitem Env: List the values of environment variables exec start Launch a new process. The Powershell invoke-commmand (see su) version cannot set a file descriptor, it’s not a Windows concept export set set an environment variable file get-child file reports on the type of file by looking at its content. get-child only looks at the extension find get-child-item (use -filter, -recurse) locate a file based on pattern in it’s name finger N/A getfacl get-acl Retrieve ACL permissions grep NA General REcursive Pattern match https://devblogs.microsoft.com/scripting/use- A very poor substitute powershell-to-toggle-the-archive-bit-on- files/select-string -match head get-content -head n Retrieve the 1st n lines of a file history history Retrieve previous commands hostname $env:hostname Name of computer id $env:username Id of User. Not as much info in PowerShell because Windows is different kill stop-process Kill a process by its pid last Requires a script and admin privileges List of logins, either all or by user id less out-host -paging Paginate Output alias: oh -p ln -s new-alias, set-alias Create a symbolic link to a file locate get-command Finds available commands Not sure if PowerShell version can find the directory ls get-ChildItem List files in current directory (note aliases: gl, dir options!) man get-help Access help alias man mkdir New-Item -itemType Directory Create a new directory alias: mkdir more out-host -paging paginate output alias: oh -p mv move-item Renames a file and possibly changes its directory newgrp N/A ping test-connection Detect if a remote machine is available ping is a separate command popd popd Remove directory from the stack printf “format string” -f valuelist Format output. The details are a bit See also: write-host complex, includes date formats. ps get-process List info on current process pushd pushd Add a directory to the stack pwd get-location Display current directory aliases: gl, pwd read read-host Input a line from the terminal with a prompt rev N/A Reverses lines in a file rm Remove-Item Delete a file or files aliases: rm, ri, rmdir, rd, del rmdir Remove-item Delete a directory alias rmdir sed N/A Stream editor setfacl set-acl Set acl file permissions sleep start-sleep Pause the current process see also Thread.sleep(n) sort sort-object Powershell sorts by properties Unix sorts using strings, fields and offsets ssh ssh (PowerShell 6) Log in to local or remote computer su New-PSSession stat get-itemProperty Show file properties tail get-content -tail n Retrieve the last n lines from a file tac sort-object Reverse the order of a command’s output Not quite the same in Powershell. One can write a script to add line #s to the output and reverse sort. tee tee-object Splits a pipeline into multiple streams test, [[ get-fileProperty Test file properties touch new-item Create a file. PowerShell does not set times tree tree Recursively show directory structure tty N/A Show current terminal ulimit N/A Shows user resource limits umask N/A Set default file permissions uname get-cimInstance System info uptime get-uptime (PowerShell 6+) Shows the uptime of current and domain linked servers *wait, wait-event In Unix this is based on signals. Events *trap see also: new-event in PowerShell are similar but have more information wc measure-object Counts words, lines and characters in a file which get-cmd - not sure if this is quite the same. Shows which version of a program will untested. be run who, $env:username show users whoami Shows current identity

*Not usually covered in CENG151, CENG200

# of commands covered at present: 65

See also: https://docs.microsoft.com/en-us/powershell/scripting/learn/understanding-important- powershell-concepts?view=powershell-7 as a start point