How to find all files in directory that contain UTF-8 BOM (byte-order mark)?
On Windows, I need to find all files in a directory that contain UTF-8 BOM (byte-order mark). Which tool can do that and how?
It can be a PowerShell script, some text editor's advanced search feature or whatever.
Solution 1:
Here is an example of a PowerShell script. It looks in the C:
path for any files where the first 3 bytes are 0xEF, 0xBB, 0xBF
.
Function ContainsBOM
{
return $input | where {
$contents = [System.IO.File]::ReadAllBytes($_.FullName)
$_.Length -gt 2 -and $contents[0] -eq 0xEF -and $contents[1] -eq 0xBB -and $contents[2] -eq 0xBF }
}
get-childitem "C:\*.*" | where {!$_.PsIsContainer } | ContainsBOM
Is it necessary to "ReadAllBytes"? Maybe reading just a few first bytes would perform better?
Fair point. Here is an updated version that only reads the first 3 bytes.
Function ContainsBOM
{
return $input | where {
$contents = new-object byte[] 3
$stream = [System.IO.File]::OpenRead($_.FullName)
$stream.Read($contents, 0, 3) | Out-Null
$stream.Close()
$contents[0] -eq 0xEF -and $contents[1] -eq 0xBB -and $contents[2] -eq 0xBF }
}
get-childitem "C:\*.*" | where {!$_.PsIsContainer -and $_.Length -gt 2 } | ContainsBOM
Solution 2:
As a side note, here's a PowerShell script that I use to strip the UTF-8 BOM charater(s) from my source files:
$files=get-childitem -Path . -Include @("*.h","*.cpp") -Recurse
foreach ($f in $files)
{
(Get-Content $f.PSPath) |
Foreach-Object {$_ -replace "\xEF\xBB\xBF", ""} |
Set-Content $f.PSPath
}
Solution 3:
If you are on an enterprise computer (like me) with restricted privileges and can't run powershell script, you can use a portable Notepad++ with PythonScript plugin to do the task, with the following script:
import os;
import sys;
filePathSrc="C:\\Temp\\UTF8"
for root, dirs, files in os.walk(filePathSrc):
for fn in files:
if fn[-4:] != '.jar' and fn[-5:] != '.ear' and fn[-4:] != '.gif' and fn[-4:] != '.jpg' and fn[-5:] != '.jpeg' and fn[-4:] != '.xls' and fn[-4:] != '.GIF' and fn[-4:] != '.JPG' and fn[-5:] != '.JPEG' and fn[-4:] != '.XLS' and fn[-4:] != '.PNG' and fn[-4:] != '.png' and fn[-4:] != '.cab' and fn[-4:] != '.CAB' and fn[-4:] != '.ico':
notepad.open(root + "\\" + fn)
console.write(root + "\\" + fn + "\r\n")
notepad.runMenuCommand("Encoding", "Convert to UTF-8 without BOM")
notepad.save()
notepad.close()
Credit goes to https://pw999.wordpress.com/2013/08/19/mass-convert-a-project-to-utf-8-using-notepad/