I have the following error when running a script in powershell in version 5.1
Below my simple script to delete files over 180 days, I've tried some solutions but I haven't found what may be the error.
(Below error translated from Portuguese to English)
"Out-File: It is not possible to validate the argument in the 'Encoding' parameter. The" files \ DeleteLogFile_21_01_2020.log "argument does not belong to the set" unknown; string; unicode; bigendianunicode; utf8; utf7; utf32; ascii; default; oem "specified by the ValidateSet attribute. Provide an argument that is in the set and try the command again. On the line: 1 character: 36 + $ Log | Out-File -Append D: \ Program files \ DeleteLogFile_ $ LogDate.log + ~~~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ CategoryInfo: InvalidData: (:) [Out-File], ParameterBindingValidationException + FullyQualifiedErrorId: ParameterArgumentValidationError, Microsoft .PowerShell.Commands.OutFileCommand "
$logPath = "D:\Program files\NICE Systems\Logs"
$nDays = 10
$startTime = Get-Date
$Extensions = "*.*"
$LogDate = (Get-Date).ToString("dd_MM_yyyy")
$Files = Get-Childitem $LogPath -Include $Extensions -Recurse | Where-Object {$_.LastWriteTime -le (Get-Date).AddDays(-$nDays)}
foreach ($File in $Files)
{
if ($NULL -ne $File )
{
$Log = "`nData e Hora da Deleção: " + $startTime + ". O arquivo " + $File + " foi deletado do sistema."
$Log | Out-File -Append D:\Program files\DeleteLogFile_$LogDate.log
Remove-Item $File.FullName | out-null
}
}
You have no quotes around the path to your log file so it's cutting it off at the first space. You can use double quotes and the variable will still be expanded. Single will not be.
$Log | Out-File -Append "D:\Program files\DeleteLogFile_$LogDate.log"
By default windows will also not allow you to write to the program files folder and this is generally not good practice.
On your Out-File line, your path has a space in it and is not surrounded with quotation marks. In PowerShell, and most scripting languages for that matter, you have to take into account Positional Parameters. Any space that is not in a string or is not followed by/preceded by a parameter (eg. -FileName C:\FileName.txt), will be assumed to precede a positional parameter.
With that said, it is trying to use "D:\Program" as the path, and "files\DeleteLogFile_$LogDate.log" as the encoding type, which is obviously not valid. To fix this, simply make the path a string by putting it in quotation marks like so:
$Log | Out-File -Append "D:\Program files\DeleteLogFile_$LogDate.log"
Related
I am making a powershell script that will be a shecdualed task on the server and that performs following things:
look in the export folder if there are export files older than 14 days and remove them ifso.
Calculated the date of yesterday and place it in a variable
Get a script, load it into a variable and adapt some arguments in it.
Extract a node out of the script into a variable and use it in the Cterm.exe application that starts afterwards.
Everything works, except the last step. The Cterm program starts, but asks a username and password. This is specified in the last variable with node of adapted script. It seems like he don't get that information and gets stuck. I want to send the content of the node to that last variable, but I get an error.
This is the error when I perform the code stepwise and another PowerShell session:
Method invocation failed because [System.String] does not contain a method named 'SelectSingleNode'.
At line:1 char:1
+ $inputscript = $tempfile.SelectSingleNode("//Text")
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : InvalidOperation: (:) [], RuntimeException
+ FullyQualifiedErrorId : MethodNotFound
This is the complete script:
#Place arguments in defined variables:
$filelocation="C:\temp" #E on the servers
$exportdestination="C:\temp"
$tempfile= ("D:\temp\temp-file.txt")
Write-Output $filelocation
$instanceName="GCS"
#Check if there are files (in the output folder) older then 14 days and remove them:
$limit = (Get-Date).AddDays(-15)
# Delete files older than the $limit.
$removedfile= Get-ChildItem -Path $exportdestination -Recurse -Force | Where-Object { !$_.PSIsContainer -and $_.CreationTime -lt $limit }
try {
$removedfile | remove-Item -Force
}
catch {
{Write-Output "error: Not all the files could be removed!"}
}
#Export the file with the data of yesterday using the RAT script:
$yesterday=(Get-Date).AddDays(-1).ToString("yyyy-MM-dd")
write-output "hello world"
$script= [xml](Get-Content C:\CTWS_export_infinity_v1.6.04.dms)
write-output "hello world"
$script -Replace ':startDate', $yesterday -Replace ':endDate', $yesterday -Replace ':filename', ($exportdestination+"\"+$instanceName)| Out-File -FilePath $tempfile
write-output "hello world"
#| Set-Content C:\CTWS_export_infinity_v1.6.04_$yesterday.dms
#$scripttemp = C:\CTWS_export_infinity_v1.6.04_$yesterday.dms
#Start-Process -FilePath "D:\CobasInfinity\HealthShare\bin\CTerm.exe" -ArgumentList #("/console=cn_ap:$instanceName $filelocation\temp-file.txt _SYSTEM INFINITY") -wait
$inputscript = $tempfile.SelectSingleNode("//Text")
& "D:\CobasInfinity\HealthShare\bin\CTerm.exe" /console=cn_ap:$instanceName $inputscript
#Remove-Item -Path $tempfile
How can I solve that final error?
I tried to save the content as an xml in the variable,
I tried to select one node of that variable,
I used 'hello world' prints to follow the progress of the script,
I tried to check the script by doing it step by step in another PowerShell session to see where to problem is.
How can I solve that final error?
I modified PowerShell script from PowerShell - Batch change files encoding To UTF-8.
# Modified version of https://stackoverflow.com/q/18684793
[Threading.Thread]::CurrentThread.CurrentUICulture = 'en-US'
$Encoding = New-Object System.Text.UTF8Encoding($True) # If UTF8Encoding($False), It will be UTF-8 without BOM
$source = "C:\Users\AKULA\Desktop\SRC" # source directory
$destination = "C:\Users\AKULA\Desktop\DST" # destination directory
if (!(Test-Path $destination)) {
New-Item -Path $destination -ItemType Directory | Out-Null
}
# Delete all previously generated file
Get-ChildItem -Path $destination -Include * -File -Recurse | ForEach-Object {$_.Delete()}
# Recursively convert all files into UTF-8
foreach ($i in Get-ChildItem $source -Force -Recurse -Exclude "desktop.ini") {
if ($i.PSIsContainer) {
continue
}
$name = $i.Fullname.Replace($source, $destination)
$content = Get-Content $i.Fullname
if ($null -ne $content) {
[System.IO.File]::WriteAllLines($name, $content, $Encoding)
} else {
Write-Host "No content from: $i"
}
}
But after using it, I've found that PS cannot handle [ or ] well.
I made some test files that has diversity in name/content.
Get-Content : An object at the specified path C:\Users\AKULA\Desktop\SRC\FILENAME[[[[[[]]]]]]]].txt does not exist, or
has been filtered by the -Include or -Exclude parameter.
At C:\Users\AKULA\Desktop\Convert_to_UTF-8.ps1:24 char:16
+ $content = Get-Content $i.Fullname
+ ~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (System.String[]:String[]) [Get-Content], Exception
+ FullyQualifiedErrorId : ItemNotFound,Microsoft.PowerShell.Commands.GetContentCommand
Since I cannot embed images in question, here is link of IMGUR album.
Full image list: https://imgur.com/a/aN1RG2L
These are what I've tested:
Test files have different names. Their name contains space, ',
[]. Also made up different language(Japanese, Korean).
These files have same content, encoded with UCS-2 BE BOM(UTF-16 BE) so
that I can check if it has re-encoded to UTF-8.
How can I make my script handle [ or ] in file name well?
tl;dr
Indeed, use of the -LiteralPath parameter is the best solution (in PowerShell (Core) v6+, you can shorten to -lp):
$content = Get-Content -LiteralPath $i.Fullname
-LiteralPath ensures that $i.Fullname is taken verbatim (literally); that is, [ and ] in the path are interpreted as themselves rather than having special meaning, as they would have as a -Path argument, due to being interpreted as a wildcard expression - note that -Path is positionally implied if you only pass a value (a string) as the first argument, as you did (Get-Content $i.FullName)
Note: This answer analogously applies to all cmdlets that have both -Path and -LiteralPath parameters, such as Set-Content, Out-File, and Set-Location.
As for what you tried:
$content = Get-Content $i.Fullname
is effectively the same as:
$content = Get-Content -Path $i.Fullname
That is, the (first) positional argument passed to Get-Content is implicitly bound to the
-Path parameter.
The -Path parameter accepts wildcard expressions to allow matching paths by patterns; in addition to support for * (any run of characters) and ? (exactly 1 character), [...] inside a wildcard pattern denotes a character set or range (e.g., [12] or [0-9]).
Therefore an actual path that contains [...], e.g., foo[10].txt, is not recognized as such, because the [10] is interpreted as a character set matching a single character that is either 1 or 0; that is foo[10].txt would match foo0.txt and foo1.txt, but not a file literally named foo[10].txt.
When (implicitly) using -Path, it is possible to escape [ and ] instances that should be interpreted verbatim, namely via the backtick (`), but note that this can get tricky to get right when quoting and/or variable references are involved.
If you know a path to be a literal path, it is best to form a habit of using -LiteralPath (which in PowerShell Core you can shorten to -lp).
However, if your path contains literal [ and ] and you also need wildcard matching, you must use `-escaping - see this answer.
There are at least two situations where the solution's good advice doesn't hold, unfortunately.
Selective error handling
Get-Content -LiteralPath "nobox[]" gives an error message and exception type as if wildcards are involved:
Get-Content : An object at the specified path box[] does not exist, or has been filtered by the -Include or -Exclude parameter.
At line:1 char:1
+ Get-Content -Path "nobox[]"
+ ~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (System.String[]:String[]) [Get-Content], Exception
+ FullyQualifiedErrorId : ItemNotFound,Microsoft.PowerShell.Commands.GetContentCommand
whereas without the brackets, we get:
Get-Content : Cannot find path 'nobox' because it does not exist.
At line:1 char:1
+ Get-Content -LiteralPath "nobox"
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (nobox:String) [Get-Content], ItemNotFoundException
+ FullyQualifiedErrorId : PathNotFound,Microsoft.PowerShell.Commands.GetContentCommand
Therefore, to silently deal with an optional file, something like:
try {
$lines = Get-Content -LiteralPath $path -ErrorAction Stop
}
catch [System.Management.Automation.ItemNotFoundException] {
$lines = #()
}
chokes on paths with brackets.
Creating a hard or symbolic link
A minor and a major caveat:
The Path parameter, the name of the new item, "works like the LiteralPath parameter of other cmdlets", says the documentation of New-Item clearly, and that seems true and makes sense. Though I wish we could clarify that by writing -LiteralPath.
The Value parameter, the target of the link (also known as Target secretly in v5 and openly later), does not accept wildcard characters according to the same documentation, but that's a lie. The command:
New-Item -ItemType "HardLink" -Path "whatever" -Target "*"
makes Powershell squeal "Cannot set the location because path '*' resolved to multiple containers.".
So you always need the escapes for the target. If you have a file named "f[]", then this will display an error:
New-Item -ItemType "HardLink" -Path "whatever" -Target "f[]"
and this will create a link:
New-Item -ItemType "HardLink" -Path "f[2]" -Target ([WildcardPattern]::Escape("f[]"))
Same for ItemType "SymbolicLink".
I modified PowerShell script from PowerShell - Batch change files encoding To UTF-8.
# Modified version of https://stackoverflow.com/q/18684793
[Threading.Thread]::CurrentThread.CurrentUICulture = 'en-US'
$Encoding = New-Object System.Text.UTF8Encoding($True) # If UTF8Encoding($False), It will be UTF-8 without BOM
$source = "C:\Users\AKULA\Desktop\SRC" # source directory
$destination = "C:\Users\AKULA\Desktop\DST" # destination directory
if (!(Test-Path $destination)) {
New-Item -Path $destination -ItemType Directory | Out-Null
}
# Delete all previously generated file
Get-ChildItem -Path $destination -Include * -File -Recurse | ForEach-Object {$_.Delete()}
# Recursively convert all files into UTF-8
foreach ($i in Get-ChildItem $source -Force -Recurse -Exclude "desktop.ini") {
if ($i.PSIsContainer) {
continue
}
$name = $i.Fullname.Replace($source, $destination)
$content = Get-Content $i.Fullname
if ($null -ne $content) {
[System.IO.File]::WriteAllLines($name, $content, $Encoding)
} else {
Write-Host "No content from: $i"
}
}
But after using it, I've found that PS cannot handle [ or ] well.
I made some test files that has diversity in name/content.
Get-Content : An object at the specified path C:\Users\AKULA\Desktop\SRC\FILENAME[[[[[[]]]]]]]].txt does not exist, or
has been filtered by the -Include or -Exclude parameter.
At C:\Users\AKULA\Desktop\Convert_to_UTF-8.ps1:24 char:16
+ $content = Get-Content $i.Fullname
+ ~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (System.String[]:String[]) [Get-Content], Exception
+ FullyQualifiedErrorId : ItemNotFound,Microsoft.PowerShell.Commands.GetContentCommand
Since I cannot embed images in question, here is link of IMGUR album.
Full image list: https://imgur.com/a/aN1RG2L
These are what I've tested:
Test files have different names. Their name contains space, ',
[]. Also made up different language(Japanese, Korean).
These files have same content, encoded with UCS-2 BE BOM(UTF-16 BE) so
that I can check if it has re-encoded to UTF-8.
How can I make my script handle [ or ] in file name well?
tl;dr
Indeed, use of the -LiteralPath parameter is the best solution (in PowerShell (Core) v6+, you can shorten to -lp):
$content = Get-Content -LiteralPath $i.Fullname
-LiteralPath ensures that $i.Fullname is taken verbatim (literally); that is, [ and ] in the path are interpreted as themselves rather than having special meaning, as they would have as a -Path argument, due to being interpreted as a wildcard expression - note that -Path is positionally implied if you only pass a value (a string) as the first argument, as you did (Get-Content $i.FullName)
Note: This answer analogously applies to all cmdlets that have both -Path and -LiteralPath parameters, such as Set-Content, Out-File, and Set-Location.
As for what you tried:
$content = Get-Content $i.Fullname
is effectively the same as:
$content = Get-Content -Path $i.Fullname
That is, the (first) positional argument passed to Get-Content is implicitly bound to the
-Path parameter.
The -Path parameter accepts wildcard expressions to allow matching paths by patterns; in addition to support for * (any run of characters) and ? (exactly 1 character), [...] inside a wildcard pattern denotes a character set or range (e.g., [12] or [0-9]).
Therefore an actual path that contains [...], e.g., foo[10].txt, is not recognized as such, because the [10] is interpreted as a character set matching a single character that is either 1 or 0; that is foo[10].txt would match foo0.txt and foo1.txt, but not a file literally named foo[10].txt.
When (implicitly) using -Path, it is possible to escape [ and ] instances that should be interpreted verbatim, namely via the backtick (`), but note that this can get tricky to get right when quoting and/or variable references are involved.
If you know a path to be a literal path, it is best to form a habit of using -LiteralPath (which in PowerShell Core you can shorten to -lp).
However, if your path contains literal [ and ] and you also need wildcard matching, you must use `-escaping - see this answer.
There are at least two situations where the solution's good advice doesn't hold, unfortunately.
Selective error handling
Get-Content -LiteralPath "nobox[]" gives an error message and exception type as if wildcards are involved:
Get-Content : An object at the specified path box[] does not exist, or has been filtered by the -Include or -Exclude parameter.
At line:1 char:1
+ Get-Content -Path "nobox[]"
+ ~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (System.String[]:String[]) [Get-Content], Exception
+ FullyQualifiedErrorId : ItemNotFound,Microsoft.PowerShell.Commands.GetContentCommand
whereas without the brackets, we get:
Get-Content : Cannot find path 'nobox' because it does not exist.
At line:1 char:1
+ Get-Content -LiteralPath "nobox"
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (nobox:String) [Get-Content], ItemNotFoundException
+ FullyQualifiedErrorId : PathNotFound,Microsoft.PowerShell.Commands.GetContentCommand
Therefore, to silently deal with an optional file, something like:
try {
$lines = Get-Content -LiteralPath $path -ErrorAction Stop
}
catch [System.Management.Automation.ItemNotFoundException] {
$lines = #()
}
chokes on paths with brackets.
Creating a hard or symbolic link
A minor and a major caveat:
The Path parameter, the name of the new item, "works like the LiteralPath parameter of other cmdlets", says the documentation of New-Item clearly, and that seems true and makes sense. Though I wish we could clarify that by writing -LiteralPath.
The Value parameter, the target of the link (also known as Target secretly in v5 and openly later), does not accept wildcard characters according to the same documentation, but that's a lie. The command:
New-Item -ItemType "HardLink" -Path "whatever" -Target "*"
makes Powershell squeal "Cannot set the location because path '*' resolved to multiple containers.".
So you always need the escapes for the target. If you have a file named "f[]", then this will display an error:
New-Item -ItemType "HardLink" -Path "whatever" -Target "f[]"
and this will create a link:
New-Item -ItemType "HardLink" -Path "f[2]" -Target ([WildcardPattern]::Escape("f[]"))
Same for ItemType "SymbolicLink".
The desired output is to convert all of the 5 tildes into a new line character.
The command is
Powershell (Get-Content -Raw allactsconv.txt) "-replace '~~~~~', "[\r\n]" | Out-File -FilePath allactsconv.txt -Force -Encoding ascii"
It returns
At line:1 char:55
+ (Get-Content -Raw allactsconv.txt) -replace '~~~~~', [\r\n] | Out-Fil ...
+ ~
Missing type name after '['.
At line:1 char:53
+ (Get-Content -Raw allactsconv.txt) -replace '~~~~~', [\r\n] | Out-Fil ...
+ ~
Missing expression after ','.
At line:1 char:54
+ (Get-Content -Raw allactsconv.txt) -replace '~~~~~', [\r\n] | Out-Fil ...
+ ~~~~~~
Unexpected token '[\r\n]' in expression or statement.
+ CategoryInfo : ParserError: (:) [], ParentContainsErrorRecordException
+ FullyQualifiedErrorId : MissingTypename
I thought the problem might be the square brackets but the error is exactly the same without them.
The better solution would be to rewrite the entire batch file (it does a lot of other stuff) as a powershell script, but unfortunately I need to fix this now. At some point I will do that.
It looks like the problem is the double quotes within the double quotes, but how do I fix that? Would like to use a powershell command if I can as I need to learn it.
Based purely upon the strings you've indicated you want to replace and wish to replace them with, I'd offer the following options:
Powershell -NoProfile "(Get-Content -Raw \".\allactsconv.txt\") -Replace \"~~~~~\", \"[`r`n]\" | Out-File -FilePath \".\allactsconv.txt\" -Force -Encoding ASCII"
If you prefer to use single quotes, in PowerShell, (not my preference), then:
Powershell -NoProfile "(Get-Content -Raw '.\allactsconv.txt') -Replace '~~~~~', '[`r`n]' | Out-File -FilePath '.\allactsconv.txt' -Force -Encoding ASCII"
I modified PowerShell script from PowerShell - Batch change files encoding To UTF-8.
# Modified version of https://stackoverflow.com/q/18684793
[Threading.Thread]::CurrentThread.CurrentUICulture = 'en-US'
$Encoding = New-Object System.Text.UTF8Encoding($True) # If UTF8Encoding($False), It will be UTF-8 without BOM
$source = "C:\Users\AKULA\Desktop\SRC" # source directory
$destination = "C:\Users\AKULA\Desktop\DST" # destination directory
if (!(Test-Path $destination)) {
New-Item -Path $destination -ItemType Directory | Out-Null
}
# Delete all previously generated file
Get-ChildItem -Path $destination -Include * -File -Recurse | ForEach-Object {$_.Delete()}
# Recursively convert all files into UTF-8
foreach ($i in Get-ChildItem $source -Force -Recurse -Exclude "desktop.ini") {
if ($i.PSIsContainer) {
continue
}
$name = $i.Fullname.Replace($source, $destination)
$content = Get-Content $i.Fullname
if ($null -ne $content) {
[System.IO.File]::WriteAllLines($name, $content, $Encoding)
} else {
Write-Host "No content from: $i"
}
}
But after using it, I've found that PS cannot handle [ or ] well.
I made some test files that has diversity in name/content.
Get-Content : An object at the specified path C:\Users\AKULA\Desktop\SRC\FILENAME[[[[[[]]]]]]]].txt does not exist, or
has been filtered by the -Include or -Exclude parameter.
At C:\Users\AKULA\Desktop\Convert_to_UTF-8.ps1:24 char:16
+ $content = Get-Content $i.Fullname
+ ~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (System.String[]:String[]) [Get-Content], Exception
+ FullyQualifiedErrorId : ItemNotFound,Microsoft.PowerShell.Commands.GetContentCommand
Since I cannot embed images in question, here is link of IMGUR album.
Full image list: https://imgur.com/a/aN1RG2L
These are what I've tested:
Test files have different names. Their name contains space, ',
[]. Also made up different language(Japanese, Korean).
These files have same content, encoded with UCS-2 BE BOM(UTF-16 BE) so
that I can check if it has re-encoded to UTF-8.
How can I make my script handle [ or ] in file name well?
tl;dr
Indeed, use of the -LiteralPath parameter is the best solution (in PowerShell (Core) v6+, you can shorten to -lp):
$content = Get-Content -LiteralPath $i.Fullname
-LiteralPath ensures that $i.Fullname is taken verbatim (literally); that is, [ and ] in the path are interpreted as themselves rather than having special meaning, as they would have as a -Path argument, due to being interpreted as a wildcard expression - note that -Path is positionally implied if you only pass a value (a string) as the first argument, as you did (Get-Content $i.FullName)
Note: This answer analogously applies to all cmdlets that have both -Path and -LiteralPath parameters, such as Set-Content, Out-File, and Set-Location.
As for what you tried:
$content = Get-Content $i.Fullname
is effectively the same as:
$content = Get-Content -Path $i.Fullname
That is, the (first) positional argument passed to Get-Content is implicitly bound to the
-Path parameter.
The -Path parameter accepts wildcard expressions to allow matching paths by patterns; in addition to support for * (any run of characters) and ? (exactly 1 character), [...] inside a wildcard pattern denotes a character set or range (e.g., [12] or [0-9]).
Therefore an actual path that contains [...], e.g., foo[10].txt, is not recognized as such, because the [10] is interpreted as a character set matching a single character that is either 1 or 0; that is foo[10].txt would match foo0.txt and foo1.txt, but not a file literally named foo[10].txt.
When (implicitly) using -Path, it is possible to escape [ and ] instances that should be interpreted verbatim, namely via the backtick (`), but note that this can get tricky to get right when quoting and/or variable references are involved.
If you know a path to be a literal path, it is best to form a habit of using -LiteralPath (which in PowerShell Core you can shorten to -lp).
However, if your path contains literal [ and ] and you also need wildcard matching, you must use `-escaping - see this answer.
There are at least two situations where the solution's good advice doesn't hold, unfortunately.
Selective error handling
Get-Content -LiteralPath "nobox[]" gives an error message and exception type as if wildcards are involved:
Get-Content : An object at the specified path box[] does not exist, or has been filtered by the -Include or -Exclude parameter.
At line:1 char:1
+ Get-Content -Path "nobox[]"
+ ~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (System.String[]:String[]) [Get-Content], Exception
+ FullyQualifiedErrorId : ItemNotFound,Microsoft.PowerShell.Commands.GetContentCommand
whereas without the brackets, we get:
Get-Content : Cannot find path 'nobox' because it does not exist.
At line:1 char:1
+ Get-Content -LiteralPath "nobox"
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : ObjectNotFound: (nobox:String) [Get-Content], ItemNotFoundException
+ FullyQualifiedErrorId : PathNotFound,Microsoft.PowerShell.Commands.GetContentCommand
Therefore, to silently deal with an optional file, something like:
try {
$lines = Get-Content -LiteralPath $path -ErrorAction Stop
}
catch [System.Management.Automation.ItemNotFoundException] {
$lines = #()
}
chokes on paths with brackets.
Creating a hard or symbolic link
A minor and a major caveat:
The Path parameter, the name of the new item, "works like the LiteralPath parameter of other cmdlets", says the documentation of New-Item clearly, and that seems true and makes sense. Though I wish we could clarify that by writing -LiteralPath.
The Value parameter, the target of the link (also known as Target secretly in v5 and openly later), does not accept wildcard characters according to the same documentation, but that's a lie. The command:
New-Item -ItemType "HardLink" -Path "whatever" -Target "*"
makes Powershell squeal "Cannot set the location because path '*' resolved to multiple containers.".
So you always need the escapes for the target. If you have a file named "f[]", then this will display an error:
New-Item -ItemType "HardLink" -Path "whatever" -Target "f[]"
and this will create a link:
New-Item -ItemType "HardLink" -Path "f[2]" -Target ([WildcardPattern]::Escape("f[]"))
Same for ItemType "SymbolicLink".