Shrink transaction log files for all databases in SQL Server

USE master;

/* Note **
If a datatabase has more than one transaction log file,
each will have this target size.
*/
DECLARE @target_size_mb NVARCHAR(20) = 100;

DECLARE @SQL NVARCHAR(4000);
SET @SQL = '

USE [?]

DECLARE @Updateability NVARCHAR(100)
SET @Updateability = CAST(DATABASEPROPERTYEX(''?'', ''Updateability'') AS NVARCHAR(100))

IF @Updateability = ''READ_WRITE ''
BEGIN
   RAISERROR(''INFO: Shrinking transaction log of database: %s'', 10, 1, ''?'')

   -- open a cursor so we can iterate through and shrink all log files
   RAISERROR(''INFO: Truncate all transaction log files.....'', 10, 1) WITH NOWAIT;
   DECLARE @log_file_name sysname;
   DECLARE c1 cursor for
   SELECT name from sys.database_files where type=1;
   OPEN c1;
   FETCH c1 into @log_file_name;
   WHILE @@FETCH_STATUS = 0
   BEGIN
   	   RAISERROR(''INFO: Truncating transaction log file %s....'', 10, 1, @log_file_name) WITH NOWAIT; 
   	   DBCC SHRINKFILE (@log_file_name, ' + @target_size_mb +');
   	   FETCH c1 into @log_file_name;
   END
   CLOSE c1;
   DEALLOCATE c1;
   PRINT ''''
END
ELSE
   RAISERROR(''Skipping "database" %s in Updateability mode "%s"'', 10, 1,  ''?'',  @Updateability) 
'
PRINT @SQL

exec sp_MSforeachdb @SQL;