Write in hosts

I use this:

RequestExecutionLevel admin
......


......


ExecWait "$INSTDIR\x.bat"



In x.bat i have

IF EXIST %windir%\SYSTEM32\DRIVERS\ETC\HOSTS*.* ATTRIB +A -H -R -S %windir%\SYSTEM32\DRIVERS\ETC\HOSTS*.* > NUL

echo 127.0.0.1 something.com >> %windir%\system32\drivers\etc\hosts


....


I tried on XP. work OK.

In Win7-10/64 work random.
Most more didn't work.

I tried run installer (in installer exist command RequestExecutionLevel admin). never ask for rights.
I tried too RunAsAdministrator (rightclik)..

If i try "Runn as administrator on Total commander, go to hosts, F4-edit, made the change, save, work correctly.

Where is the misjate?

Thank you

There might be some 64-bit path issues here, try running Process Monitor from Sysinternals/Microsoft...

What is the reason you are doing this from a separate BAT file rather than directly in NSIS?

Thank you, i'll try this.

But...what mean $4 from this commands?
(FileOpen $4...)

Originally Posted by alibabavl64 View Post

But...what mean $4 from this commands?
(FileOpen $4...)

$4 is the register (variable) where the file handle is stored.

You should read the entire documentation before asking basic questions like this.

This command...

FileOpen $4 "SomeFile.txt" a 

...tries to open "SomeFile.txt", in append mode. And, if successful, it stores the file handle in user variable $4.

Use the IfErrors command in order to check whether file was opened successfully.

See here for details:

@Anders
1. I never sed "i am guru". If i was a guru maybe didn't ask.
2. My english is not so good.
3. http://nsis.sourceforge.net/Docs/Chapter4.html#fileinst
here wrote:
"FileOpen

user_var(handle output) filename openmode

Opens a file named "filename", and sets the handle output variable with the handle. The openmode should be one of "r" (read) "w" (write, all contents of file are destroyed) or "a" (append, meaning opened for both read and write, contents preserved). In all open modes, the file pointer is placed at the beginning of the file. If the file cannot be opened, the handle output is set to empty, and the error flag is set."

I understud that handle is automaticaly set but not specify if is a problemm if i use

Fileopen $0
Fileopen $1
Fileopen $5
Fileopen $1000

That $x is chosen by me and must only be the same in a sequence to the same file, or must choose respect another rule?

@Lord:
Thank you

Originally Posted by alibabavl64 View Post

I understud that handle is automaticaly set but not specify if is a problemm if i use

Fileopen $0
Fileopen $1
Fileopen $5
Fileopen $1000

That $x is chosen by me and must only be the same in a sequence to the same file, or must choose respect another rule?

$x is the name of the variable where the result is stored!

NSIS provides the variables $0 to $9 as well as $R0 to $R9 by default. There is no $1000, but you can define your own variables.

Read the manual:

Thank you, Lord Mulder.

Thank you again, work fine!

I understud that after write in "hosts" a command "ipconfig /flushdns" is mandatory.

Is possible directly or need something like "execdos" plugin?

Thank you.

Originally Posted by alibabavl64 View Post

I understud that after write in "hosts" a command "ipconfig /flushdns" is mandatory.

Is possible directly or need something like "execdos" plugin?

Thank you.

Try nsExec, it is part of the default NSIS install...

thank you

Hy, i need your help again.

I need write few lines in .....\etc\hosts.
If hosts exist, write without problems.
But i has an Win10 HOME EDITION and me myself see in \etc\ the file named "hosts" not exist.

1. Please how can verify first if exist (is correct
SetOutPath "$Windir\system32\drivers\etc"
SetFileAttributes "hosts" 0
FileOpen $0 "hosts" a
If errors ???(how create a file named "hosts"?)

Or exist another command for find the file?
Because i found somewhere "FileOpen $0 "hosts" a" will create a new file named hosts but to me not happend..
Run as admin is activated and installer was run "Run As Administrator"..
2. If Home Edition of Windows haven't this "hosts" file, IF i create and populate with 127.0.0.1 www.myweb.xx, that page will be blocked too or that method don't work in "Home edition"? Another method?

Thank you

!include LogicLib.nsh
Section
${If} ${FileExists} "C:\something"
  #...
${Else} 
  #...
${EndIf}
SectionEnd 

but FileOpen should work, the a mode calls CreateFile with OPEN_ALWAYS

Originally Posted by Anders View Post

but FileOpen should work, [...]

Yes, in W10 64 PRO work perfectly. But in that version, Home Edition, didn't work.

Try running Process Monitor and see why FileOpen fails on these systems...

Thank you, i'll try this.

Need help again:

Let say i installed once my programm.
Uninstall and reinstall.
In this case in hosts will be twice the "locked" pages.

(i don't agree overwrite method, in hosts can be links used by another programs, i think adblock plus and few solutions for cryptolocker prevent use hosts).

I want i check if in hosts i wrote a line like "127.0.0.1 xyz.abc" and if exist, do nothing and if not exist, append.

An idea for checking?
Thank you

You can look at Appendix E in the help file and see if you can use any of the helper functions. If not, there is always plain FileRead + StrCpy & StrCmp to do manual string parsing but NSIS is never going to be the best way to edit text files.