Write txt first line instead of last - vba

Question

It is easy to find in the internet a way of write into a txt file but all I find is always writing in the very last line:
Sub write_log(sentence_to_be_written As String)
Dim strFile_Path As String
strFile_Path = "C:\Users\[user_name]\Desktop\log.txt"
Open strFile_Path For Append As #1
Print #1, Now() & " --> " & sentence_to_be_written
Close #1
End Sub
I would like to write instead into the first line of the txt file.

Answer 1

Try the next code, please. It needs a reference to Microsoft Scripting Runtime. It can be adapted to work without such a reference. In fact, I will also post a pice of code able to automatically add the necessary reference... It is possible to read the text using standard VBA Open, but only concatenating line by line and I think this solution is more elegant:
Sub write_log_OnTop(sentence_to_be_written As String)
'It neds a reference to 'Microsoft Script Runtime'
Dim strFile_Path As String, strText As String
Dim fso As New FileSystemObject, txtStr As TextStream
strFile_Path = "C:\Users\Fane Branesti\OneDrive\Desktop\log.txt"
If Dir(strFile_Path) <> "" Then 'check if file exists
Set txtStr = fso.OpenTextFile(strFile_Path)
strText = txtStr.ReadAll
txtStr.Close
Else
MsgBox "Wrong file path...": Exit Sub
End If
strText = Now() & " --> " & sentence_to_be_written & vbCrLf & strText
Open strFile_Path For Output As #1
Print #1, strText
Close #1
End Sub
And Microsoft Scripting Runtime reference can be automatically add by running of the next code:
Private Sub Add_Scripting_Reference() 'Adds 'Microsoft Scripting Runtime'
Dim wb As Workbook, r As Reference
Set wb = ThisWorkbook
For Each r In wb.VBProject.References
If r.name = "Scripting" Then Exit Sub
Next
wb.VBProject.References.AddFromFile Environ("windir") & "\system32\scrrun.dll"
End Sub
If you do not want the reference, even if I would not understand such a choice, it is enough to comment/replace the code line
Dim fso As New FileSystemObject, txtStr As TextStream
with:
Dim fso As Object, txtStr As Object: Set fso = CreateObject("Scripting.FileSystemObject")

Answer 2

There is no command to add text at the top (or the middle) of any file. I never heard about such command in any programming language. It's about (disk-)space management, if you add a line of text in front of any other text, the existing text needs to be moved, and this is a rather complicated operation.
If you deal with short files, you could solve that by reading the content of the file into memory and then recreate the file by first writing the new line(s) and the add the content - as Joerg Wood suggested in the comments. However, this would need lot of memory and/or disk IO if the file gets larger, and the process has to be repeated every time you want to add a line - maybe not an issue if you write only one line per hour, but quite an issue if you are writing multiple lines per second.
It seems you are writing a log file and probably you want to see what was going on lately. You could use a windows version of the tail command (that comes from Unix) or use the powershell command Get-Content "C:\Users\[user_name]\Desktop\log.txt" -Tail 10 (see https://stackoverflow.com/a/188126/7599798) for that - it will display the last lines of a file.
An alternative could be to write the log into an Excel sheet or a database - in both cases it is easy to fetch the data in any order.