Need to substitute \x0d\x0a to \x2c\x0d\x0a in a file using powershell

Question

Need to replace \x0d\x0a with \x2c\x0d\x0a in a file.

I can do it relatively easy on Unix:

awk '(NR>1){gsub("\r$",",\r")}1' $file > "fixed_$file":

Need help with implementing this in PowerShell.

Thank you in advance.

Answer 1

Assuming that you're running this on Windows (where \r\n (CRLF) newlines are the default), the following command is the equivalent of your awk command:

Get-Content $file | ForEach-Object { 
  if ($_.ReadCount -eq 1) { $_ } else { $_ -replace '$', ',' }
} | Set-Content "fixed_$file"

Caveat: The character encoding of the input file is not preserved, and Set-Content uses a default, which you can override with -Encoding.
In Windows PowerShell, this default is the system's "ANSI" encoding, whereas in PowerShell Core it is BOM-less UTF-8.

• Get-Content $file reads the input file line by line.

• The ForEach-Object loop passes the 1st line ($_.ReadCount -eq 1) through as-is ($_), and appends , (which is what escape sequence \x2c in your awk command represents) to all others ($_ -replace '$', ',').

  • Note: $_ + ',' or "$_," are simpler alternatives for appending a comma; the regex-based
    -replace operator was used here to highlight the PowerShell feature that is similar to awk's gsub().

• Set-Content then writes the resulting lines to the target file, terminating each with the platform-appropriate newline sequence, which on Windows is CRLF (\r\n).