HP OpenVMS Systems Documentation

OpenVMS Utility Routines Manual

Use the INHERIT attribute to access the LBR and CRE symbols from SYS$LIBRARY:STARLET.PEN.
Start the declarations of the LBR routines that are used by the program. Each argument to be passed to the Librarian is specified on a separate line and includes the name (which just acts as a placeholder) and data type (for example: UNSIGNED, which means an unsigned integer value, and PACKED ARRAY OF CHAR, which means a character string). If the argument is preceded by VAR, then a value for that argument is returned by the LBR to the program.
Declare the procedure Open_Error, which is called in the executable section if the Librarian returns an error when LBR$OPEN is called. Open_Error checks the Librarian's return status value to determine the specific cause of the error. The return status values for each routine are listed in the descriptions of the routines.
Initialize the array called Options with the values the Librarian needs to create the library.
Call LBR$INI_CONTROL, specifying that the function to be performed is create and that the library type is text.
Call LBR$OPEN to create and open the library; pass the Options array initialized in item 5 to the Librarian.
If the call to LBR$OPEN was unsuccessful, call the procedure Open_Error (see item 4) to determine the cause of the error.

12.2.2 Inserting a Module

Example 12-2 illustrates the insertion of a module into a library from a Compaq Pascal program. The program is summarized in the following steps:

Ensure that the module does not already exist by calling LBR$LOOKUP_KEY. The return status should be LBR$_KEYNOTFND. This step is optional.
Construct the module by calling LBR$PUT_RECORD once for each record going into the module. Pass the contents of the record as the second argument. LBR$PUT_RECORD returns the record file address (RFA) in the library file as the third argument on the first call. On subsequent calls, you pass the RFA as the third argument, so do not alter its value between calls.
Call LBR$PUT_END after the last call to LBR$PUT_RECORD.
Call LBR$INSERT_KEY to catalog the records you have just put in the library. The second argument is the name of the module.

To replace an existing module, save the RFA of the module header returned by LBR$LOOKUP_KEY in Step 1 in one variable and the new RFA returned by the first call to LBR$PUT_RECORD (Step 2) in another variable. In Step 4, invoke LBR$REPLACE_KEY instead of LBR$INSERT_KEY, pass the old RFA as the third argument, and the new RFA as the fourth argument.

Example 12-2 Inserting a Module into a Library Using Compaq Pascal

PROGRAM insertmod(INPUT,OUTPUT);
                (*This program inserts a module into a library*)
TYPE
    Rfa_Ptr = ARRAY [0..1] OF INTEGER;  (*Data type of RFA of module*)
VAR
    LBR$C_UPDATE,                       (*Constants for LBR$INI_CONTROL*)
    LBR$C_TYP_TXT,                        (*Defined in $LBRDEF macro*)
    LBR$_KEYNOTFND : [EXTERNAL] INTEGER;(*Error code for LBR$LOOKUP_KEY*)
    Lib_Name : VARYING [128] OF CHAR;   (*Name of library receiving module*)
    Module_Name : VARYING [31] OF CHAR; (*Name of module to insert*)
    Text_Data_Record : VARYING [255] OF CHAR; (*Record in new module*)
    Textin : FILE OF VARYING [255] OF CHAR; (*File containing new module*)
    lib_index_ptr : UNSIGNED;           (*Value returned in library init*)
    status : UNSIGNED;                  (*Return status for function calls*)
    txtrfa_ptr : Rfa_Ptr;               (*For key lookup and insertion*)
    Key_Not_Found : BOOLEAN := FALSE;   (*True if new mod not already in lib*)
                (*-*-*-*-Function Definitions-*-*-*-*)
                                        (*Function that returns library
                                        control index used by Librarian*)
FUNCTION LBR$INI_CONTROL (VAR library_index: UNSIGNED;
                          func: UNSIGNED;
                          typ: UNSIGNED;
                          VAR namblk: ARRAY[l..u:INTEGER]
                                OF INTEGER := %IMMED 0):
        INTEGER; EXTERN;
                                        (*Function that creates/opens library*)
FUNCTION LBR$OPEN  (library_index: UNSIGNED;
                   fns: [class_s]PACKED ARRAY[l..u:INTEGER] OF CHAR;
                   create_options: ARRAY [l2..u2:INTEGER] OF INTEGER :=
                        %IMMED 0;
                   dns: [CLASS_S] PACKED ARRAY [l3..u3:INTEGER] OF CHAR
                        := %IMMED 0;
                   rlfna: ARRAY [l4..u4:INTEGER] OF INTEGER := %IMMED 0;
                   rns: [CLASS_S] PACKED ARRAY [l5..u5:INTEGER] OF CHAR :=
                        %IMMED 0;
                   VAR rnslen: INTEGER := %IMMED 0):
        INTEGER; EXTERN;
                                        (*Function that finds a key in index*)
FUNCTION LBR$LOOKUP_KEY (library_index: UNSIGNED;
                         key_name:[CLASS_S] PACKED ARRAY [l..u:INTEGER] OF
                               CHAR;
                         VAR txtrfa: Rfa_Ptr):
        INTEGER; EXTERN;
                                        (*Function that inserts key in index*)
FUNCTION LBR$INSERT_KEY (library_index: UNSIGNED;
                         key_name:[CLASS_S] PACKED ARRAY [l..u:INTEGER] OF
                               CHAR;
                         txtrfa: Rfa_Ptr):
        INTEGER; EXTERN;
                                        (*Function that writes data records*)

FUNCTION LBR$PUT_RECORD (library_index: UNSIGNED;              (*to modules*)
                         textline:[CLASS_S] PACKED ARRAY [l..u:INTEGER] OF
                               CHAR;
                        txtrfa: Rfa_Ptr):
        INTEGER; EXTERN;
                                        (*Function that marks end of a module*)
FUNCTION LBR$PUT_END (library_index: UNSIGNED):
        INTEGER; EXTERN;
                                        (*Function that closes library*)
FUNCTION LBR$CLOSE (library_index: UNSIGNED):
        INTEGER; EXTERN;
BEGIN  (* *************** DECLARATIONS COMPLETE *************************
        *************** MAIN PROGRAM BEGINS HERE ********************** *)
                                        (*Prompt for library name and
                                        module to insert*)
    WRITE('Library Name: '); READLN(Lib_Name);
    WRITE('Module Name:  '); READLN(Module_Name);
                                        (*Initialize lib for update access*)
    status := LBR$INI_CONTROL   (lib_index_ptr,     (1)
                                IADDRESS(LBR$C_UPDATE),    (*Update access*)
                                IADDRESS(LBR$C_TYP_TXT));  (*Text library*)
    IF NOT ODD(status) THEN             (*Check error status*)
        WRITELN('Initialization Failed')
    ELSE                                (*Initialization was successful*)
        BEGIN
            status := LBR$OPEN  (lib_index_ptr, (*Open the library*)
                                Lib_Name);
            IF NOT ODD(status) THEN     (*Check error status*)
                WRITELN('Open Not Successful')
            ELSE                        (*Open was successful*)
                BEGIN                   (*Is module already in the library?*)
                    status := LBR$LOOKUP_KEY    (lib_index_ptr,     (2)
                                                Module_Name,
                                                txtrfa_ptr);
                    IF ODD(status) THEN (*Check status.  Should not be odd*)
                        WRITELN('Lookup key was successful.',
                                'The module is already in the library.')
                    ELSE   (*Did lookup key fail because key not found?*)
                            IF status = IADDRESS(LBR$_KEYNOTFND) THEN (3)
                                Key_Not_Found := TRUE
                END
        END;

          (******If LBR$LOOKUP_KEY failed because the key was not found
          (as expected), we can open the file containing the new module,
          and write the module's records to the library file*******)
    IF Key_Not_Found THEN
        BEGIN
            OPEN(Textin,Module_Name,old);
            RESET(Textin);
            WHILE NOT EOF(Textin) DO            (*Repeat until end of file*)
                BEGIN                        (4)
                    READ(Textin,Text_Data_Record);      (*Read record from
                                                        external file*)
                    status := LBR$PUT_RECORD    (lib_index_ptr,   (*Write*)
                                                Text_Data_Record, (*record to*)
                                                txtrfa_ptr);      (*library*)
                    IF NOT ODD(status) THEN
                        WRITELN('Put Record Routine Not Successful')
                END; (*of WHILE statement*)
            IF ODD(status) THEN (*True if all the records have been
                                successfully written into the library*)
                BEGIN
                    status := LBR$PUT_END (lib_index_ptr); (*Write end of
                                                           module record*)
                    IF NOT ODD(status) THEN
                        WRITELN('Put End Routine Not Successful')
                    ELSE                (*Insert key for new module*)
                        BEGIN                       (5)
                            status := LBR$INSERT_KEY    (lib_index_ptr,
                                                        Module_Name,
                                                        txtrfa_ptr);
                            IF NOT ODD(status) THEN
                                WRITELN('Insert Key Not Successful')
                        END
                END
        END;
    status := LBR$CLOSE(lib_index_ptr);
    IF NOT ODD(status) THEN
        WRITELN('Close Not Successful')
END. (*of program insertmod*)

Each item in the following list corresponds to a number highlighted in Example 12-2:

Call LBR$INI_CONTROL, specifying that the function to be performed is update and that the library type is text.
Call LBR$LOOKUP_KEY to see whether the module to be inserted is already in the library.
Call LBR$LOOKUP_KEY to see whether the lookup key failed because the key was not found. (In this case, the status value is LBR$_KEYNOTFND.)
Read a record from the input file, then use LBR$PUT_RECORD to write the record to the library. When all the records have been written to the library, use LBR$PUT_END to write an end-of-module record.
Use LBR$INSERT_KEY to insert a key for the module into the current index.

12.2.3 Extracting a Module

Example 12-3 illustrates the extraction of a library module from a Compaq Pascal program. The program is summarized in the following steps:

Call LBR$LOOKUP_KEY to locate the module. Specify the name of the module as the second argument. LBR$LOOKUP_KEY returns the RFA of the module as the third argument; do not alter this value.
Call LBR$GET_RECORD once for each record in the module. Specify a character string to receive the extracted record as the second argument. LBR$GET_RECORD returns a status value of RMS$_EOF after the last record in the module is extracted.

Example 12-3 Extracting a Module from a Library Using Compaq Pascal

PROGRAM extractmod(INPUT,OUTPUT,Textout);
                (*This program extracts a module from a library*)
TYPE
    Rfa_Ptr = ARRAY [0..1] OF INTEGER;  (*Data type of RFA of module*)
VAR
    LBR$C_UPDATE,                       (*Constants for LBR$INI_CONTROL*)
    LBR$C_TYP_TXT,                        (*Defined in $LBRDEF macro*)
    RMS$_EOF : [EXTERNAL] INTEGER;      (*RMS return status; defined in
                                        $RMSDEF macro*)
    Lib_Name : VARYING [128] OF CHAR;   (*Name of library receiving module*)
    Module_Name : VARYING [31] OF CHAR; (*Name of module to insert*)
    Extracted_File : VARYING [31] OF CHAR;      (*Name of file to hold
                                                extracted module*)
    Outtext : PACKED ARRAY [1..255] OF CHAR;    (*Extracted mod put here,*)
    Outtext2 : VARYING [255] OF CHAR;           (*     then moved to here*)
    i : INTEGER;                        (*For loop control*)
    Textout : FILE OF VARYING [255] OF CHAR;    (*File containing extracted
                                                module*)
    nullstring : CHAR;                  (*nullstring, pos, and len used to*)
    pos, len : INTEGER;                 (*find string in extracted file recd*)
    lib_index_ptr : UNSIGNED;           (*Value returned in library init*)
    status : UNSIGNED;                  (*Return status for function calls*)
    txtrfa_ptr : Rfa_Ptr;               (*For key lookup and insertion*)
                (*-*-*-*-Function Definitions-*-*-*-*)
                        (*Function that returns library
                        control index used by Librarian*)
FUNCTION LBR$INI_CONTROL (VAR library_index: UNSIGNED;
                          func: UNSIGNED;
                          typ: UNSIGNED;
                          VAR namblk: ARRAY[l..u:INTEGER]
                                OF INTEGER := %IMMED 0):
        INTEGER; EXTERN;
                        (*Function that creates/opens library*)
FUNCTION LBR$OPEN  (library_index: UNSIGNED;
                   fns: [class_s]PACKED ARRAY[l..u:INTEGER] OF CHAR;
                   create_options: ARRAY [l2..u2:INTEGER] OF INTEGER :=
                        %IMMED 0;
                   dns: [CLASS_S] PACKED ARRAY [l3..u3:INTEGER] OF CHAR
                        := %IMMED 0;
                   rlfna: ARRAY [l4..u4:INTEGER] OF INTEGER := %IMMED 0;
                   rns: [CLASS_S] PACKED ARRAY [l5..u5:INTEGER] OF CHAR :=
                        %IMMED 0;
                   VAR rnslen: INTEGER := %IMMED 0):
        INTEGER; EXTERN;
                        (*Function that finds a key in an index*)
FUNCTION LBR$LOOKUP_KEY (library_index: UNSIGNED;
                         key_name:[CLASS_S] PACKED ARRAY [l..u:INTEGER] OF
                               CHAR;
                         VAR txtrfa: Rfa_Ptr):
        INTEGER; EXTERN;

                        (*Function that retrieves records from modules*)
FUNCTION LBR$GET_RECORD (library_index: UNSIGNED;
                         var textline:[CLASS_S] PACKED ARRAY [l..u:INTEGER] OF
                               CHAR):
                        INTEGER;
EXTERN;
                        (*Function that closes library*)
FUNCTION LBR$CLOSE (library_index: UNSIGNED):
        INTEGER; EXTERN;
BEGIN  (* *************** DECLARATIONS COMPLETE *************************
        *************** MAIN PROGRAM BEGINS HERE ********************** *)
 (* Get Library Name, Module To Extract, And File To Hold Extracted Module *)
    WRITE('Library Name: '); READLN(Lib_Name);
    WRITE('Module Name:  '); READLN(Module_Name);
    WRITE('Extract Into File: '); READLN(Extracted_File);

    status := LBR$INI_CONTROL   (lib_index_ptr,     (1)
                                IADDRESS(LBR$C_UPDATE),
                                IADDRESS(LBR$C_TYP_TXT));
    IF NOT ODD(status) THEN
        WRITELN('Initialization Failed')
    ELSE
        BEGIN
            status := LBR$OPEN  (lib_index_ptr,
                                Lib_Name);
            IF NOT ODD(status) THEN
                WRITELN('Open Not Successful')
            ELSE
                BEGIN                         (2)
                    status := LBR$LOOKUP_KEY    (lib_index_ptr,
                                                Module_Name,
                                                txtrfa_ptr);
                    IF NOT ODD(status) THEN
                        WRITELN('Lookup Key Not Successful')
                    ELSE
                        BEGIN                 (3)
                            OPEN(Textout,Extracted_File,new);
                            REWRITE(Textout)
                        END
                END
        END;
    WHILE ODD(status) DO
        BEGIN
            nullstring := ''(0);
            FOR i := 1 TO 255 DO              (4)
                Outtext[i] := nullstring;
            status := LBR$GET_RECORD    (lib_index_ptr,
                                        Outtext);
            IF NOT ODD(status) THEN
                BEGIN                         (5)
                    IF status = IADDRESS(RMS$_EOF) THEN
                        WRITELN('  RMS end of file')
                END

            ELSE
                BEGIN                        (6)
                    pos := INDEX(Outtext, nullstring);  (*find first null
                                                        in Outtext*)
                    len := pos - 1;     (*length of Outtext to first null*)
                    IF len >= 1 THEN
                        BEGIN
                            Outtext2 := SUBSTR(Outtext,1,LEN);
                            WRITE(Textout,Outtext2)
                        END
                END
        END; (*of WHILE*)
    status := LBR$CLOSE(lib_index_ptr);
    IF NOT ODD(status) THEN
        WRITELN('Close Not Successful')
END. (*of program extractmod*)

Each item in the following list corresponds to a number highlighted in Example 12-3:

Call LBR$INI_CONTROL, specifying that the function to be performed is update and that the library type is text.
Call LBR$LOOKUP_KEY to find the key that points to the module you want to extract.
Open an output file to receive the extracted module.
Initialize the variable that is to receive the extracted records to null characters.
Call LBR$GET_RECORD to see if there are more records in the file (module). A failure indicates that the end of the file has been reached.
Write the extracted record data to the output file. This record should consist only of the data up to the first null character.

12.2.4 Deleting a Module

Example 12-4 illustrates the deletion of library module from a Compaq Pascal program. The program is summarized in the following steps:

Call LBR$LOOKUP_KEY, and specify the name of the module as the second argument. LBR$LOOKUP_KEY returns the RFA of the module as the third argument; do not alter this value.
Call LBR$DELETE_KEY to delete the module key. Specify the name of the module as the second argument.
Call LBR$DELETE_DATA to delete the module itself. Specify the RFA of the module obtained in Step 1 as the second argument.

Example 12-4 Deleting a Module from a Library Using Compaq Pascal

PROGRAM deletemod(INPUT,OUTPUT);
        (*This program deletes a module from a library*)
TYPE
    Rfa_Ptr = ARRAY [0..1] OF INTEGER;  (*Data type of RFA of module*)
VAR
    LBR$C_UPDATE,                       (*Constants for LBR$INI_CONTROL*)
    LBR$C_TYP_TXT,                        (*Defined in $LBRDEF macro*)
    LBR$_KEYNOTFND : [EXTERNAL] INTEGER;(*Error code for LBR$LOOKUP_KEY*)
    Lib_Name : VARYING [128] OF CHAR;   (*Name of library receiving module*)
    Module_Name : VARYING [31] OF CHAR; (*Name of module to insert*)
    Text_Data_Record : VARYING [255] OF CHAR; (*Record in new module*)
    Textin : FILE OF VARYING [255] OF CHAR; (*File containing new module*)
    lib_index_ptr : UNSIGNED;           (*Value returned in library init*)
    status : UNSIGNED;                  (*Return status for function calls*)
    txtrfa_ptr : Rfa_Ptr;               (*For key lookup and insertion*)
    Key_Not_Found : BOOLEAN := FALSE;   (*True if new mod not already in lib*)
                (*-*-*-*-Function Definitions-*-*-*-*)
                                (*Function that returns library
                                control index used by Librarian*)
FUNCTION LBR$INI_CONTROL (VAR library_index: UNSIGNED;
                          func: UNSIGNED;
                          typ: UNSIGNED;
                          VAR namblk: ARRAY[l..u:INTEGER]
                                OF INTEGER := %IMMED 0):
        INTEGER; EXTERN;
                                (*Function that creates/opens library*)
FUNCTION LBR$OPEN  (library_index: UNSIGNED;
                   fns: [class_s]PACKED ARRAY[l..u:INTEGER] OF CHAR;
                   create_options: ARRAY [l2..u2:INTEGER] OF INTEGER :=
                        %IMMED 0;
                   dns: [CLASS_S] PACKED ARRAY [l3..u3:INTEGER] OF CHAR
                        := %IMMED 0;
                   rlfna: ARRAY [l4..u4:INTEGER] OF INTEGER := %IMMED 0;
                   rns: [CLASS_S] PACKED ARRAY [l5..u5:INTEGER] OF CHAR :=
                        %IMMED 0;
                   VAR rnslen: INTEGER := %IMMED 0):
        INTEGER; EXTERN;
                                (*Function that finds a key in index*)
FUNCTION LBR$LOOKUP_KEY (library_index: UNSIGNED;
                         key_name:[CLASS_S] PACKED ARRAY [l..u:INTEGER] OF
                               CHAR;
                         VAR txtrfa: Rfa_Ptr):
        INTEGER; EXTERN;
                                (*Function that removes a key from an index*)
FUNCTION LBR$DELETE_KEY (library_index: UNSIGNED;
                         key_name:[CLASS_S] PACKED ARRAY [l..u:INTEGER] OF
                               CHAR):
                         INTEGER;
EXTERN;

                                (*Function that deletes all the records
                                associated with a module*)
FUNCTION LBR$DELETE_DATA (library_index: UNSIGNED;
                         txtrfa: Rfa_Ptr):
                         INTEGER;
EXTERN;
                                (*Function that closes library*)
FUNCTION LBR$CLOSE (library_index: UNSIGNED):
        INTEGER; EXTERN;

BEGIN  (* *************** DECLARATIONS COMPLETE *************************
        *************** MAIN PROGRAM BEGINS HERE ********************** *)
                                (* Get Library Name and Module to Delete *)
    WRITE('Library Name: '); READLN(Lib_Name);
    WRITE('Module Name:  '); READLN(Module_Name);
                                        (*Initialize lib for update access*)
    status := LBR$INI_CONTROL   (lib_index_ptr,         (1)
                                IADDRESS(LBR$C_UPDATE),    (*Update access*)
                                IADDRESS(LBR$C_TYP_TXT));  (*Text library*)
    IF NOT ODD(status) THEN             (*Check error status*)
        WRITELN('Initialization Failed')
    ELSE                                (*Initialization was successful*)
        BEGIN
            status := LBR$OPEN  (lib_index_ptr, (*Open the library*)
                                Lib_Name);
            IF NOT ODD(status) THEN     (*Check error status*)
                WRITELN('Open Not Successful')
            ELSE                        (*Open was successful*)
                BEGIN        (2)  (*Is module in the library?*)
                    status := LBR$LOOKUP_KEY    (lib_index_ptr,
                                                Module_Name,
                                                txtrfa_ptr);
                    IF NOT ODD(status) THEN (*Check status*)
                        WRITELN('Lookup Key Not Successful')
                END
        END;
    IF ODD(status) THEN                 (*Key was found; delete it*)
        BEGIN
            status := LBR$DELETE_KEY    (lib_index_ptr,    (3)
                                        Module_Name);
            IF NOT ODD(status) THEN
                WRITELN('Delete Key Routine Not Successful')
            ELSE                        (*Delete key was successful*)
                BEGIN                   (*Now delete module's data records*)
                    status := LBR$DELETE_DATA   (lib_index_ptr,    (4)
                                                txtrfa_ptr);
                    IF NOT ODD(status) THEN
                        WRITELN('Delete Data Routine Not Successful')
                END
        END;
    status := LBR$CLOSE(lib_index_ptr); (*Close the library*)
    IF NOT ODD(status) THEN
        WRITELN('Close Not Successful');
END. (*of program deletemod*)

Each item in the following list corresponds to a number highlighted in Example 12-4:

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