c# - Creating file then setting timestamp without releasing file lock -

i know if there way create file , set last write time (and other timestamp information) without allowing process acquire lock file between these 2 operations.

the reason want fix issue antivirus acquires lock file after has been created , still has lock time file attributes being attempted set. code working sevenzipsharp (no longer maintained far can see).

code reproduces issue is:

var filepath = "test.txt"; using (var filestream = new filestream(filepath, filemode.create, fileaccess.readwrite)) {     var bytes = encoding.ascii.getbytes("hello fail.");     filestream.write(bytes, 0, bytes.length);     var fileinfo = new fileinfo(filepath);     fileinfo.creationtime = datetime.now; } 

this produces following exception when executing last statement: system.io.ioexception "the process cannot access file 'c:\test.txt' because being used process."

i considering implementing setting of time attributes retry mechanism, wondered if there more elegant solution.

as @damien_the_unbeliever mentioned, need file handle. try this.

class program {     [dllimport("kernel32.dll", setlasterror = true)]     [return: marshalas(unmanagedtype.bool)]     static extern bool setfiletime(safefilehandle hfile, ref long lpcreationtime, ref long lplastaccesstime, ref long lplastwritetime);      static void main(string[] args) {         var filepath = "test.txt";         long when = datetime.now.adddays(10).tofiletime();         using (var filestream = new filestream(filepath, filemode.create, fileaccess.readwrite)) {             if (!setfiletime(filestream.safefilehandle, ref when, ref when, ref when)) {                 throw new win32exception();             }             var bytes = encoding.ascii.getbytes("hello fail.");             filestream.write(bytes, 0, bytes.length);         }     } }