I'm trying to parse a binary file, and I need some help on where to go. I've looking online for "parsing binary files", "reading binary files", "reading text inside binaries", etc. and I haven't had any luck.
For example, how would I read this text out of this binary file? Any help would be MUCH appreciated. I am using powershell.
It seems that you have a binary file with text on a fixed or otherwise deducible position. Get-Content might help you but... It'll try to parse the entire file to an array of strings and thus creating an array of "garbage". Also, you wouldn't know from what file position a particular "rope of characters" was.
You can try .NET classes File to read and Encoding to decode. It's just a line for each call:
# Read the entire file to an array of bytes.
$bytes = [System.IO.File]::ReadAllBytes("path_to_the_file")
# Decode first 12 bytes to a text assuming ASCII encoding.
$text = [System.Text.Encoding]::ASCII.GetString($bytes, 0, 12)
In your real case you'd probably go through the array of bytes in a loop finding the start and end of a particular string sequence and using those indices to specify the range of bytes you want to extract the text from by the GetString.
The .NET methods I mentioned are available in .NET Framework 2.0 or higher. If you installed PowerShell 2.0 you already have it.
You can read in the file via Get-Content -Encoding byte . I'm not sure how to parse it though.
Get-Content ... -Encoding Byte -Raw which returns [System.Byte[]] instead of [System.Object[]] but otherwise is handled exactly the same.
byte isn’t supported in PowerShell 6.
byte isn't supported as of PS6 since, strictly, it is not a character encoding. The functionality is still available by specifying -AsByteStream instead of -Encoding. Reading the entire file into a variable results in an Object[] of the bytes (or an actual Byte[] if -Raw used) which can then be processed as desired. In the example, the strings (note the embedded '\0') could be obtained by -join [char[]]$bytearray[0xe00..0xe11] and -join [char[]]$bytearray[0xe13..0xe54]. The method used rather depends upon what is meant by parse a binary file.If you're just looking for strings, check out the strings.exe utility from SysInternals.
There is an example on microsoft.com here:
$byteArray = Get-Content -Path C:\temp\test.txt -AsByteStream -Raw
Get-Member -InputObject $bytearray
After this we can do whatever we want with the data.
I prefer to omit -Raw and deal with the array.
So I could for example write:
$byteArray = Get-Content -Path C:\temp\test.txt -AsByteStream -TotalCount 50 | where { $_ -gt 32 -and $_ -lt 128 }
[System.Text.Encoding]::UTF8.GetString($byteArray)
