Using Powershell v2 called from a batch file, I want to replace each CRLF in a file with just an LF. If a file only has LF without any CR, then I want all the LF to be left alone.
I do not want a terminating CRLF in the resultant file, if possible.
I found this question here on Stack Overflow, that seems to be a close match, but it does not specify a Powershell version requirement, nor does it specify the other criteria above. Hence this question.
The accepted answer for that question recommends this code:
$in = "C:\Users\abc\Desktop\File\abc.txt"
$out = "C:\Users\abc\Desktop\File\abc-out.txt"
(Get-Content $in) -join "`n" > $out
I slightly modified it, and adjusted it to work from within a batch file, to read:
powershell -Command "(Get-Content file1.txt) -join '`n' > file2.txt"
Unfortunately, this does not work. All LF's are converted to the string `n.
How can I get this to work?
Those before me are right you should use "`n"
When using PowerShell I recommend executing it the following switches:
-noninteractive indicate you do not want to interact with the powershell
-NoProfile - speeds up the things considerably (skips loading profile)
-ExecutionPolicy Bypass - bypasses security issues if you are on companies environment
Edit:
Sorry about the mistake you mentioned. I now have PowerShell 2.0 testing facility.
The fixed your example (the mistake was that you have to escape the double quotes due to the powershell.exe interpreting them). This approach does not work completely as it leaves CRLF at the end of the file:
powershell.exe -noninteractive -NoProfile -ExecutionPolicy Bypass -Command "& {(Get-Content file_crlf.txt) -join \"`n\" > file_lfonly.txt};"
However, the completely correct solution needs different approach (via IO.file class):
powershell.exe -noninteractive -NoProfile -ExecutionPolicy Bypass -Command "& {[IO.File]::WriteAllText('file_lfonly.txt', ([IO.File]::ReadAllText('file_crlf.txt') -replace \"`r`n\", \"`n\"))};"
This completely converts your CRLF to LF. Just small piece of warning it converts to ASCII not Unicode (out of scope of this question).
All examples are now tested on PowerShell v2.0.50727.
A couple of things:
Single quotes ' are literal - use double quotes " so that PowerShell knows you mean new line
If you need to escape double quotes within double quotes, use "" or `"
Edit:
Your original post worked for me, so looks like this is related to PowerShell 5 v 2, and I am unable to test the solution. Instead of escape characters, here is a solution using scriptblock:
powershell -Command {(Get-Content file1.txt) -join "`n" > file2.txt}
It's worth noting that this is trivial in Notepad++ and can be done for multiple files at once:
Related
This is a deceptively complex issue, but I'll do my best to explain the problem.
I have a simple wrapper script as follows called VSYSCopyPathToClipboard.ps1:
param (
[Parameter(Mandatory,Position = 0)]
[String[]]
$Path,
[Parameter(Mandatory=$false)]
[Switch]
$FilenamesOnly,
[Parameter(Mandatory=$false)]
[Switch]
$Quotes
)
if($FilenamesOnly){
Copy-PathToClipboard -Path $Path -FilenamesOnly
}else{
Copy-PathToClipboard -Path $Path
}
Copy-PathToClipboard is just a function I have available that copies paths/filenames to the clipboard. It's irrelevant to the issue, just assume it does what it says.
The way the wrapper is called is through the Windows right click context menu. This involves creating a key here: HKEY_CLASSES_ROOT\AllFilesystemObjects\shell\.
Mine looks like this:
The command is as follows:
"C:\Tools\scripts\BIN\SingleInstanceAccumulator.exe" -q:' "-c:pwsh -noprofile -windowstyle hidden -Command "C:\Tools\scripts\VSYSCopyPathToClipboard.ps1" -Path $files" "%1"
And similarly for the "Copy as Filename":
"C:\Tools\scripts\BIN\SingleInstanceAccumulator.exe" -q:' "-c:pwsh -noprofile -windowstyle hidden -Command "C:\Tools\scripts\VSYSCopyPathToClipboard.ps1" -FilenamesOnly -Path $files" "%1"
I am using a tool here called SingleInstanceAccumulator. This allows me to pass multiple selected files to a single instance of PowerShell. If I didn't use this program and ran my command with multiple files selected it would launch multiple instances of PowerShell for each file selected. It's the next best thing to creating your own shell extension and implementing IPC etc.
This has been working great until today when I encountered a file with a single quote in its filename (I.E.testing'video.mov) and the entire script failed. It's failing because the delimiter I'm using with SingleInstanceAccumulator is also a single quote and PowerShell sees no matching quote... thus errors out.
I could fix this if my variables were static by just doubling up the offending single quote, but since my parameters are files I have no opportunity to escape the single quote beyond renaming the file itself ... which is a non-solution.
So now I have no clue how to handle this.
My first try at solving the problem was as such:
Create a batch file and redirect my registry command to it.
Change the SingleInstanceAccumulator delimiter to '/' (All files will be separated by a forward slash.)
Replace the offending single quote to two single quotes.
Replace the '/' delimiters with single quotes.
Finally pass the whole argument list back to Powershell.
This image demonstrates how the above process looks:
This is the batch file's code:
#echo off
setlocal EnableDelayedExpansion
:: This script is needed to escape filenames that have
:: a single quote ('). It's replaced with double single
:: quotes so the filenames don't choke powershell
:: echo %cmdcmdline%
set "fullpath=%*"
echo Before
echo !fullpath!
echo ""
echo After
set fullpath=%fullpath:'=''%
set fullpath=%fullpath:/='%
echo !fullpath!
:: pwsh.exe -noprofile -windowstyle hidden -command "%~dpn0.ps1 -Path !fullpath!
pause
Once I got that wired up I started celebrating ... until I hit a file with an ampersand (&) or an exclamation point (!). Everything fell apart again. I did a whole bunch of google-fu with regards to escaping the & and ! characters but nothing suggested worked at all for me.
If I pass 'C:\Users\futur\Desktop\Testing\Video Files\MOV Batch\testing&video.mov' into my batch file, I get 'C:\Users\futur\Desktop\Testing\Video Files\MOV Batch\testing back.
It truncates the string at the exact position of the ampersand.
I feel like there has to be a way to solve this, and that I'm missing something stupid. If I echo %cmdcmdline% it shows the full commandline with the &, so it's available somehow with that variable.
In conclusion: I'm sorry for the novel of a post. There is a lot of nuance in what I'm trying to accomplish that needs to be explained. My questions are as follows:
Can I accomplish this with Powershell only and somehow pre-escape single quotes?
Can I accomplish this with a batch file, and somehow pre-escape & and ! (and any other special characters that would cause failure)?
Any help at all would be hugely appreciated.
Edit1:
So in the most hideous and hackish way possible, I managed to solve my problem. But since it's so horrible and I feel horrible for doing it I am still looking for a proper solution.
Basically, to recap, when I do either of these variable assignments:
set "args=%*"
set "args=!%*!"
echo !args!
& and ! characters still break things, and I don't get a full enumeration of my files. Files with & get truncated, etc.
But I noticed when I do:
set "args=!cmdcmdline!"
echo !args!
I get the full commandline call with all special characters retained:
C:\WINDOWS\system32\cmd.exe /c ""C:\Tools\scripts\VSYSCopyPathToClipboardTest.bat" /C:\Users\futur\Desktop\Testing\Video Files\MOV Batch\KylieCan't.mov/,/C:\Users\futur\Desktop\Testing\Video Files\MOV Batch\The !Rodinians - Future Forest !Fantasy - FFF Trailer.mov/,/C:\Users\futur\Desktop\Testing\Video Files\MOV Batch\Yelle - Je Veu&x Te Voir.mov/,/C:\Users\futur\Desktop\Testing\Video Files\MOV Batch\Erik&Truffaz.mov/,/C:\Users\futur\Desktop\Testing\Video Files\MOV Batch\my_file'name.mov/,/C:\Users\futur\Desktop\Testing\Video Files\MOV Batch\testing&video.mov/"
So what I did was simply strip out the initial C:\WINDOWS\system32\cmd.exe /c ""C:\Tools\scripts\VSYSCopyPathToClipboardTest.bat" part of the string:
#echo off
setlocal enableDelayedExpansion
set "args=!cmdcmdline!"
set args=!args:C:\WINDOWS\system32\cmd.exe=!
set args=!args: /c ""C:\Tools\scripts\VSYSCopyPathToClipboard.bat" =!
set args=!args:'=''!
set args=!args:/='!
set args=!args:~0,-1!
echo !args!
pwsh.exe -noprofile -noexit -command "%~dpn0.ps1 -Path !args!
And... it works flawlessly. It handles any crazy character I throw at it without needing to escape anything. I know It's totally the most degenerate garbage way of approaching this, but not finding a solution anywhere leads me to desperate measures. :)
I am probably going to make the string removal a bit more universal since it literally breaks if I change the filename.
I am still VERY much open to other solutions should anyone know of a way to accomplish the same thing in a more elegant way.
A fully robust solution based on PowerShell's -Command (-c) CLI parameter that can handle ' characters in paths as well as $ and ` ones requires a fairly elaborate workaround, unfortunately:[1]
Use an aux. cmd.exe call that echoes the $files macro as-is and pipe that to pwsh.exe; make SingleInstanceAccumulator.exe double-quote the individual paths (as it does by default), but use no delimiter (d:"") in order to effectively output a string in the form "<path 1>""<path 2>""...
Make pwsh.exe reference the piped input via the automatic $input variable and split it into an array of individual paths by " (removing empty elements that are a side effect of splitting with -ne ''). The necessity for providing the paths via the pipeline (stdin) is discussed in more detail in this related answer.
The resulting array can safely be passed to your scripts.
Also, enclose the entire -Command (-c) argument passed to pwsh.exe in \"...\" inside the "-c:..." argument.
Note: You may get away without doing this; however, this would result in whitespace normalization, which (however unlikely) would alter a file named, say, foo bar.txt to foo bar.txt (the run of multiple spaces was normalized to a single space).
Escaping " characters as \" is necessary for PowerShell's -Command (-c) CLI parameter to treat them verbatim, as part of the PowerShell code to execute that is seen after initial command-line parsing, during which any unescaped " characters are stripped.
Therefore, the first command stored in the registry should be (adapt the second one analogously; note that there must be no space between the echo $files and the subsequent |):
"C:\Tools\scripts\BIN\SingleInstanceAccumulator.exe" -d:"" "-c:cmd /c echo $files| pwsh.exe -noprofile -c \"& 'C:\Tools\scripts\VSYSCopyPathToClipboard.ps1' -Path ($input -split '\\\"' -ne '')\"" "%1"
Note:
If you modified your scripts to accept the paths as individual arguments rather than as an array, a much simpler solution via the -File CLI parameter (rather than -Command (-c)) is possible. This could be as simple as decorating the $Path parameter declaration with [Parameter(ValueFromRemainingArguments)] and then invoking the script without naming the target parameter explicitly (-Path):
"C:\Tools\scripts\BIN\SingleInstanceAccumulator.exe" -d:" " "-c:pwsh.exe -noprofile -File \"C:\Tools\scripts\VSYSCopyPathToClipboard.ps1\" $files" "%1"
Note the use of -d:" " to make SingleInstanceAccumulator.exe space-separate the (double-quoted by default) paths. Since -File passes the pass-through arguments verbatim, there is no concern about what characters the paths are composed of.
Self-contained PowerShell sample code:
The following code defines a Copy Paths to Clipboard shortcut-menu command for all file-system objects (except drives):
No separate .ps1 script is involved; instead, the code passed to -Command / -c directly performs the desired operation (copying the paths passed to the clipboard).
The following helps with troubleshooting:
The full command line with which PowerShell was invoked ([Environment]::CommandLine) is printed, as is the list of paths passed ($file)
-windowstyle hidden is omitted to keep the console window in which the PowerShell commands visible and -noexit is added so as to keep the window open after the command has finished executing.
Prerequisites:
Download and build the SingleInstanceAccumulator project using Visual Studio (using the .NET SDK is possible, but requires extra work).
Place the resulting SingleInstanceAccumulator.exe file in one of the directories listed in your $env:Path environment variable. Alternatively, specify the full path to the executable below.
Note:
reg.exe uses \ as its escape character, which means that \ characters that should become part of the string stored in the registry must be escaped, as \\.
The sad reality as of PowerShell 7.2 is that an extra, manual layer of \-escaping of embedded " characters is required in arguments passed to external programs. This may get fixed in a future version, which may require opt-in. See this answer for details. The code below does this by way of a -replace '"', '\"' operation, which can easily be removed if it should no longer be necessary in a future PowerShell version.
# RUN WITH ELEVATION (AS ADMIN).
# Determine the full path of SingleInstanceAccumulator.exe:
# Note: If it isn't in $env:PATH, specify its full path instead.
$singleInstanceAccumulatorExe = (Get-Command -ErrorAction Stop SingleInstanceAccumulator.exe).Path
# The name of the shortcut-menu command to create for all file-system objects.
$menuCommandName = 'Copy Paths To Clipboard'
# Create the menu command registry key.
$null = reg.exe add "HKEY_CLASSES_ROOT\AllFilesystemObjects\shell\$menuCommandName" /f /v "MultiSelectModel" /d "Player"
if ($LASTEXITCODE) { throw }
# Define the command line for it.
# To use *Windows PowerShell* instead, replace "pwsh.exe" with "powershell.exe"
# SEE NOTES ABOVE.
$null = reg.exe add "HKEY_CLASSES_ROOT\AllFilesystemObjects\shell\$menuCommandName\command" /f /ve /t REG_EXPAND_SZ /d (#"
"$singleInstanceAccumulatorExe" -d:"" "-c:cmd /c echo `$files| pwsh.exe -noexit -noprofile -c \\"[Environment]::CommandLine; `$paths = `$input -split [char] 34 -ne ''; `$paths; Set-Clipboard `$paths\\"" "%1"
"# -replace '"', '\"')
if ($LASTEXITCODE) { throw }
Write-Verbose -Verbose "Shortcut menu command '$menuCommandName' successfully set up."
Now you can right-click on multiple files/folders in File Explorer and select Copy Paths to Clipboard in order to copy the full paths of all selected items to the clipboard in a single operation.
[1] An alternative is to use the -f option instead, which causes SingleInstanceAccumulator.exe to write all file paths line by line to an auxiliary text file, and then expands $files to that file's full path. However, this requires the target scripts to be designed accordingly, and it is their responsibility to clean up the auxiliary text file.
I have this command that works ok on powershell
Compare-Object (Get-Content "tex1.txt") (Get-Content "tex2.txt") | Where-Object{$_.SideIndicator -eq "<="} | select inputobject | ft -hidetableheaders
I'm trying to running in cmd by doing this:
powershell -Command " & {Compare-Object (Get-Content "tex1.txt") (Get-Content "tex2.txt") | Where-Object{$_.SideIndicator -eq "<="} | select inputobject | ft -hidetableheaders}"
but it says something like: the name, the directory or the volume syntax is incorrect (is in spanish so i dont know the exact translation)
I think the problem is the pipes, since running everything before the pipe: Compare-Object (Get-Content "tex1.txt") (Get-Content "tex2.txt") works
PD: I also tried to write ^ before the pipes but I haven't succeeded.
tl;dr
When calling the PowerShell CLI (powershell.exe for Windows PowerShell, pwsh for the cross-platform PowerShell [Core] 6+ edition):
Using embedded " in an overall "..." string comes with escaping challenges.
If feasible for a given command, formulating it without embedded " is the easiest solution:
powershell -Command "Compare-Object (Get-Content tex1.txt) (Get-Content tex2.txt) | Where-Object {$_.SideIndicator -eq '<='} | select inputobject | ft -hidetableheaders"
Read on, if you do need to use embedded ".
eryksun points out that your problem is your lack of escaping of embedded " chars. inside the overall "..." string, which causes cmd.exe to see multiple strings, including parts it considers unquoted, which causes problems with special characters such as | and < - they never reach PowerShell.
Nesting double-quote strings from cmd.exe is tricky business:
To make cmd.exe happy, you need to double the embedded " chars. ("")
Separately, to make powershell.exe happy, you need to \-escape " chars.
Note: PowerShell [Core] 6+, the cross-platform edition, on Windows now also accepts "" by itself, which is the most robust choice.
Generally, dealing with quoting and escaping arguments when calling from cmd.exe is a frustrating experience with no universal solutions, unlike in the Unix world. Sadly, PowerShell has its own challenges, even in the Unix world.[1]
In short: Escape embedded " chars. when calling the Windows PowerShell CLI, powershell.exe, from cmd.exe as follows (for the PowerShell (Core) 7+ CLI, pwsh.exe, "" is the robust choice):
Use "^"" (sic) when using powershell.exe -Command, which works robustly.
Caveat: "^"" does not work for calling other programs.
This saves you from additional escaping, as would be necessary if you used \"
Example: powershell -command " Write-Output "^""a & b"^"" " yields a & b, as expected, and the & didn't need escaping.
If you use the simpler - and customary - \", you may need to perform additional escaping: Specifically, you must individually ^-escape the following cmd.exe metacharacters with ^ inside \"...\" runs: & | < > ^Thanks, LotPings.
Example: powershell -command " Write-Output \"a ^& b\" " yields a & b; that is, the & needed escaping with ^.
Additionally, to treat % (and, with enabledelayedexpansion , !) verbatim, the escaping syntax unfortunately depends on whether you're calling from the command line or a batch file: use %^USERNAME% (!^USERNAME) from the former, and %%USERNAME%% (^!USERNAME^! / ^^!USERNAME^^! inside \"...\" runs) from the latter - see this answer for the gory details.
It is unfortunate that cmd.exe makes use of \" treacherous, given that it is supported by virtually all programs (except batch files), and if it weren't for these extra escaping requirements, command lines that use it have the potential to work across different platforms and shells - with the notable exception of calling from PowerShell, where, sadly, an additional layer of escaping is needed and " inside "..." must be escaped as \`" (sic); see this answer.
See the bottom section for ways to ease the escaping pain by avoiding use of nested ".
Other programs, including PowerShell Core:
Use just "" for programs compiled with Microsoft compilers and, on Windows, also Python and Node.js as well as PowerShell Core (pwsh.exe).
Regrettably, this robust option does not work with powershell.exe, i.e. Windows PowerShell.
Use \" for programs with Unix heritage, such as Perl and Ruby - which comes with the escaping headaches discussed above.
Avoiding embedded ":
When you call PowerShell's CLI, you can often get away without needing to embed double quotes:
There may be arguments in your string that don't require quoting at all, such as text1.txt and text2.txt
You can alternatively use single-quoting ('...') inside the overall command string, which require no escaping; note that such strings, from PowerShell's perspective, are string literals.
To put it all together:
powershell -Command "Compare-Object (Get-Content tex1.txt) (Get-Content tex2.txt) | Where-Object {$_.SideIndicator -eq '<='} | select inputobject | ft -hidetableheaders"
Note that I've also removed the & { ... } around your command, as it isn't necessary.
[1] eryksun puts it as follows: "This is the inescapable frustration of the Windows command line. Every program parses its own command line, using whatever rules it wants. So the syntax of a command line has to work with not only the shell (CMD) but also all programs invoked in the pipeline. In the Unix world the shell parses the command line into argv arrays, so typically you only have to get the syntax right to make the shell happy."
The problems with PowerShell Core, even on Unix, stem from how it re-quotes arguments behind the scenes before passing them on - see this GitHub docs issue.
I'm trying to run a PowerShell script from Windows cmd.exe. The input to the PowerShell script is a string, which contains newline characters using PowerShell backtick escaping - i.e:
`r`n
For demonstration purposes, the input string is then written to the console, and also dumped to a file.
The issue I have is that when the script is run from cmd.exe using the syntax
powershell.exe script.ps1 "TEST`r`nTEST"
The newline characters in the string are not treated as newline, and are included literally in both the console output and the output text file.
TEST`r`nTEST
However, if I run this from a PowerShell environment, I get the expected result (i.e. the newline characters are parsed correctly, and a newline is inserted in the appropriate location).
TEST
TEST
Similarly, if I pass in \r\n instead of the escaped newline characters through Windows cmd.exe, and do a .replace in the PowerShell script
$date = $data.replace("\r\n","`r`n")
I get the expected output:
TEST
TEST
Is anyone able to shed some light on why this happens?
The test script is as follows:
param([string]$data) # data to send
Write-Host $data
[IO.File]::WriteAllText('d:\temp.txt', $data)
return 0
And the file is called from the command line as:
powershell.exe script.ps1 "TEST`r`nTEST"
The script is running on Windows Server 2012 R2, using PowerShell v4.0
tl;dr
Use -Command and pass the entire PowerShell command as a single string; e.g.:
C:\> powershell -NoProfile -Command "script.ps1 \"TEST`r`nTEST\""
TEST
TEST
Note how the internal " instances are escaped as \", which PowerShell requires when called from the outside (alternatively, for full robustness, use "^"" (sic) in Windows PowerShell and "" in PowerShell (Core) v6+).
In your specific case,
powershell -NoProfile -Command script.ps1 "TEST`r`nTEST" would have worked too, but generally that only works as intended if the string has no embedded spaces.
Given that -Command is the default up to PSv5.1, your command - as currently posted - should work as-is.
As of PowerShell v5.1, arguments passed to powershell.exe from the outside:
ARE subject to interpretation by PowerShell, including string interpolation, by default and when you use -Command (i.e., specifying neither -File nor -Command currently defaults to -Command).
Caveat: The default behavior will change in v6: -File will be the default then - see the relevant change on GitHub.
are NOT subject to interpretation if you use -File to invoke a script - (after potential interpretation by cmd.exe) PowerShell treats all arguments as literal strings.
Caveat: This behavior is currently being discussed with respect to v6, given that it is overtly problematic in at least one case: trying to pass Boolean values.
Optional reading: Why you should pass the entire PowerShell command as a single argument when using -Command:
When you use -Command with multiple arguments, PowerShell essentially assembles them into a single command line behind the scenes before executing it.
Any "..."-quoting around the individual arguments is lost in the process, which can have unexpected results; e.g.:
C:\> powershell -NoProfile -Command "& { $args.count }" "line 1`r`nline 2"
3 # !! "line 1`r`nline 2" was broken into 3 arguments
Given that the outer "..." quoting was removed in the process of parsing the command line, the actual command line that PowerShell ended up executing was:
C:\ PS> & { $args.Count } line 1`r`nline 2
3
To illustrate why, let's look at an equivalent command that uses explicit quoting:
C:\ PS> & { $args.Count } "line" "1`r`nline" "2"
In other words: After the enclosing " were removed, the resulting token was broken into multiple arguments by spaces, as usual.
The parameter will need to be reinterpreted as a PowerShell string. Will this get you down the road?
The reason your -replace did not work is that the original string actually contains a backtick. It needs to be escaped in the search string.
C:\src\t>type p1.ps1
Param([string]$s)
Write-Host $s
$p = Invoke-Expression `"$s`"
Write-Host $p
$p2 = $s -replace "``r``n","`r`n"
Write-Host $p2
C:\src\t>powershell -noprofile -file .\p1.ps1 "TEST`r`nTEST"
TEST`r`nTEST
TEST
TEST
TEST
TEST
Carriage return and Linefeed are bytes with values 13 and 10, you can't write them, you can't see them.
As a convenience, when writing PowerShell code, the language will let you write:
"`r`n"
in a double quoted string, and when processing PowerShell source code (and at no other time), it will read those and replace them with bytes value 13 and 10.
It is this line of code in the PowerShell tokenizer which does it.
There is nothing special about backtick-n to the cmd.exe interpreter, and nothing special about having it in a string - you can put it there in a single quoted string
'`n'
or replacing it in a string - except that you have to note when the replacement happens. e.g. in your comment:
For example, if you pass in 'r'n and then replace 'r'n with 'r'n, the 'r'n is still output literally
Because your code
-replace "`r`n"
becomes
-replace "[char]13[char]10"
and your string passed in from outside contains
`r`n
and they don't match. Backtick-n in a string isn't magic, strings are not all interpreted by the PowerShell engine as PowerShell code, nor are parameters, or anything. And it's only in that context - when you write your -replace code, that is when the swap for actual newline characters happens.
I am trying to execute the following powershell commands from CMD, for example:
powershell Get-WmiObject Win32_PnPSignedDriver
powershell Get-WmiObject Win32_PnPSignedDriver > test.txt
which both work correctly.
But when I do a query, for example:
powershell (Get-WmiObject Win32_PnPSignedDriver | where {$_.location -like "*PCI bus 0, device 22, function 0*"}).DeviceName
I am getting this message the cause of which I can not pin down:
INFO: Could not find files for the given pattern(s)
This seems to work for me (I was seeing the same error as you originally):
powershell -command "(Get-WmiObject Win32_PnPSignedDriver | where {$_.location -like '*PCI bus 0, device 22, function 0*'}).DeviceName"
To complement the existing answers with general guidelines for passing commands to powershell.exe from cmd.exe (a Command Prompt):
Enclose the entire PowerShell command in "..." (double quotes).
This protects its contents from unwanted up-front interpretation by cmd.exe - as happened with | in this case, as explained in aschipfl's answer.
However, cmd.exe-style environment-variable references (e.g., %USERNAME%) are still expanded.
For quoting that is embedded in the PowerShell command:
Use '...' (single quotes) where feasible; this is what Mark Wragg's helpful answer does, but it is only an option if the quoted string is meant to be a literal (doesn't contain variable references or subexpressions).
If you do need embedded "...", escape it as \"...\"
Note that while inside PowerShell it is the ` (backtick) that serves as the escape character, when passing strings from the outside PowerShell requires \.
Simplified examples (run from cmd.exe):
Note that passing a command without a parameter name implies the -Command parameter; run powershell -? to see the command-line syntax.
You may also want to use -NoProfile so that the user profile isn't loaded every time.
Commands that don't need embedded quoting - simply double-quote:
powershell -noprofile "get-date"
powershell -noprofile "(get-date).Date"
powershell -noprofile "get-date | get-member"
Commands with embedded quoting - use '...' or \"...\":
powershell -noprofile "(get-date).Year -like '*17'"
powershell -noprofile "$v=17; (get-date).Year -like \"*$v\""
Commands that incorporate the value of a cmd.exe environment variable:
:: # Nothing special to do: cmd.exe expands the reference irrespective of quoting.
set "v=17"
powershell -noprofile "(get-date).Year -like '*%v%'"
:: # More robust variant that passes the value as an argument to a script block.
set "v=17"
powershell -noprofile ". { param($v) (get-date).Year -like \"*$v\" }" "%v%"
Optional reading: calling powershell from POSIX-like shells such as bash:
The above rules apply analogously, except that you'll typically use '...' (single quotes) to enclose the entire PowerShell command, which categorically prevents up-front interpretation by the shell.
Using "..." is an option if up-front expansions of shell-variable references and command substitutions are explicitly desired, but the potential for confusion is great, because both POSIX-like shells and PowerShell use sigil $ to refer to variables - it may not be obvious what is expanded when.
POSIX-like shells categorically do not support embedding ' instances in side '...' strings, which necessitates a somewhat awkward workaround (see below).
Simplified examples (run from a POSIX-like shell such as bash):
Commands that don't need embedded quoting - simply single-quote:
powershell -noprofile 'get-date'
powershell -noprofile '(get-date).Date'
powershell -noprofile 'get-date | get-member'
Commands with embedded quoting - replace embedded ' instances with '\'' (sic) and use embedded " as-is:
powershell -noprofile '(get-date).Year -like '\''*17'\'''
powershell -noprofile '$v=17; (get-date).Year -like "*$v"'
Commands that incorporate the value of a shell/environment variable:
# By using a double-quoted string, the shell expands $v up front.
v=17
powershell -noprofile "(get-date).Year -like '*$v'"
# It gets trickier if you want to reference PS variables too.
# Note how the PS variable's $ is \-escaped so that the shell doesn't interpret it.
v=$HOME
powershell -noprofile "\$HOME -eq '$v'"
# More robust variant that passes the value as an argument to a script block.
v=17
powershell -noprofile '. { param($v) (get-date).Year -like "*$v" }' "$v"
I am pretty sure that the pipe character | is the problem here, because cmd tries to process it.
Simply escape it by preceding with ^:
powershell (Get-WmiObject Win32_PnPSignedDriver ^| where {$_.location -like "*PCI bus 0, device 22, function 0*"}).DeviceName
If this code is used within a parenthesised block of code in cmd, you may need to escape the closing ) as well (the opening ( can be escaped too, but there is no need):
powershell ^(Get-WmiObject Win32_PnPSignedDriver ^| where {$_.location -like "*PCI bus 0, device 22, function 0*"}^).DeviceName
all,
I am trying to run a command in Power Shell and I am told the file does not exist as it stands right now for the Power Shell code. If I do the same in DOS, it finds the file and executes correctly. The only difference is that there is an additional open and closed double quote around the file name. Can this be done in Power Shell the same way? If so, how can this be done as I am not familiar with Power Shell.
DOS:
IF EXISTS F:\lvcecstos.CSV F:\LaserVault\ContentExpress\ContentExpress.exe /CID:1 /CSV:<b>"F:\lvcecstos.CSV"</b> /ClearSubscription
Power Shell:
Invoke-Expression -Command "F:\LaserVault\ContentExpress\ContentExpress.exe /CID:1 /CSV:<b>F:\lvcecstos.csv</b> /ClearSubscription"
Thanks in advance for any suggestions. I am told by the Laservault engineers that created this software package that we use that the double quotes around the file name is required. Doesn't make sense to me as to why though, but this is something I am unable to get around.
You can add double quotes around the file path as follows:
Invoke-Expression -Command 'F:\LaserVault\ContentExpress\ContentExpress.exe /CID:1 /CSV:"F:\lvcecstos.csv" /ClearSubscription';
Notice how the command is wrapped in single quotes instead of double quotes.
Ultimately, it depends on how the ContentExpress.exe program is interpreting the file path, though. For all you know, it could be appending the valued passed to "CSV" to the "current working directory."
You can also use the Start-Process cmdlet, instead of Invoke-Expression or Invoke-Command.
$Program = 'F:\LaserVault\ContentExpress\ContentExpress.exe';
$ArgumentList = '/CID:1 /CSV:"F:\lvcecstos.csv" /ClearSubscription';
Start-Process -Wait -NoNewWindow -FilePath $Program -ArgumentList $ArgumentList;
If you have PowerShell v3 (which you should) you could use the "magic parameter" --% (see here).
& F:\LaserVault\ContentExpress\ContentExpress.exe --% /CID:1 /CSV:"F:\lvcecstos.csv" /ClearSubscription
Otherwise trying to preserve double quotes around arguments could become very, very painful. See for instance this answer to a similar question.
$lvcecstos = "F:\lvcecstos.CSV"
If(Test-Path $lvcecstos)
{
Invoke-Expression -Command "& F:\LaserVault\ContentExpress\ContentExpress.exe /CID:1 /CSV:$lvcecstos /ClearSubscription"
}