|AS400 Interview questions and answers part17|
Q1: What is a library in AS400? What are the types of a library?
A library is an object in AS400 and it serves as a repository for other objects, there is a system library named QSYS. So, It can hold all the objects of various types in itself. There are four types of libraries.
For further information please refer to Library in AS400.
Q2: Which library gets first loaded into the system when we log in?
When we login into the IBM i machine the first library that gets loaded is QSYS and it is the main system library. For more information please refer to QSYS Library.
Q3: Is QGPL a user library or a system library?
QGPL is a user library because it contains temporary objects. For more information please refer to QGPL (General purpose library).
Q4: How can we see all the objects and their sizes in a library?
Library holds all the objects of various types. The Display Library (DSPLIB) command displays the contents of one or more specified objects and the sizes of each object in a library.
Q5: What is Source Physical File?
Source physical file is an object in AS400 which of course no doubt resides in a library. So, what does it actually contain? It basically contains the different types of source members which contain the source code either in RPG, CL, COBOL, DDS, SQL, etc. Those source members are not an object until and unless they are not compiled. For further information please refer to Source physical file in AS400.
Q6: Why do we use the EXTMBR keyword in RPGLE?
The EXTMBR in the RPGLE keyword is used to read a particular member and specifies which member of the file is opened.
Q7: What is the use of the USROPN keyword in RPGLE?
USROPN keyword is associated with the file which tells the system that when we open the file with open opcode and for closing the file with the close opcode. When the program gets initialized the file would not get open if do not use open opcode for opening that file.
Q8: When do we use 'NODEBUGIO' in AS400?
NODEBUGIO is used to avoid breaking multiple times on the IO operation when we take F10 on reading opcode during the debug. So, to avoid this condition we use NODEBUGIO in H-SPECS in the RPG program.
Q9: What is the Library list?
The Library list specifies which libraries will get searched and in what order for an object. For more information please refer to the Library list.
Q10: How many libraries can be there on the Library list?
We can have a maximum of up to 15 system libraries and 25 application libraries in the library list.