Und warum schreibst Du das Ding nicht gleich mit embedded SQL als Unicode (allerdings mit CCSID 13488) file ins IFS?

PHP-Code:
D MyDBCLOBFile    S                   SQLTYPE(DBCLOB_File)       
                   
D MyUCS2Var       S             50C   Varying                                       
D MyCharVar       S             50A   Varying                                       
D CRLF            S              2A   Inz
(x'0D25')                                  
 
//**********************************************************************************
C/Exec SQL   Set Option  Commit=*NoneDatFmt=*ISOTimFmt=*ISO,                    
C+                       Naming=*SYS,  CloSQLCsr=*EndActGrp                         
C
/End-Exec                                                                          
 
/FREE                                                                              
    MyDBCLOBFile_Name 
'/home/Hauser/TST_Unicode.txt';                             
    
MyDBCLOBFile_NL   = %Len(%Trim(MyDBCLOBFile_Name));                                    
    
MyDBCLOBFile_FO   SQFOVR;                            //Create/Replace IFS File
    
    
MyUCS2Var = %UCS2('First Text passed in Unicode');                        
    
Exec SQL Set :MyDBCLOBFile = :MyUCS2Var Concat :CRLF;                     
    If 
SQLCODE < *Zeros;                                                      
       
//Handle Error                                                         
    
EndIf;                                                                    
                                                                                
    
MyDBCLOBFile_FO   SQFAPP;                            //Add to IFS File  
    
    
MyCharVar 'Second Text passed as Character';                            
    
Exec SQL Set :MyDBCLOBFile = :MyCharVar concat :CRLF;                     
    If 
SQLCODE < *Zeros;                                                      
       
//Handle Error                                                         
    
EndIf;                                                                    
                                                                                
    
Exec SQL Set :MyDBCLOBFile 'Third Text passed dirctly' concat :CRLF;    
    If 
SQLCODE < *Zeros;                                                      
       
//Handle Error                                                         
    
EndIf;                                                                    
  *
InLR       = *On;                                                          
 /
END-FREE 
Birgitta