The script file bldmfcob, in sqllib/samples/cobol_mf, contains the commands to build a sample COBOL program.
The first parameter, $1, specifies the name of your source file. The second parameter, $2, specifies the name of the database to which you want to connect. Parameter $3 specifies the user ID for the database, and $4 specifies the password. Only the first parameter, the source file name, is required. Database name, user ID, and password are optional. If no database name is supplied, the program uses the default sample database.
#! /bin/ksh # bldmfcob script file # Builds a COBOL program containing embedded SQL # Usage: bldmfcob <prog_name> [ <db_name> [ <userid> <password> ]] # Connect to a database. if (($# < 2)) then db2 connect to sample elif (($# < 3)) then db2 connect to $2 else db2 connect to $2 user $3 using $4 fi # Precompile the program. db2 prep $1.sqb bindfile # Bind the program to the database. db2 bind $1.bnd # Disconnect from the database. db2 connect reset # Set COBCPY to include the DB2 COPY files directory. export COBCPY=/usr/lpp/db2_05_00/include/cobol_mf:$COBCPY # Compile the checkerr.cbl error checking utility. cob -c -x checkerr.cbl # Compile the program. cob -c -x $1.cbl # Link the program. cob -x -o $1 $1.o checkerr.o -ldb2 -ldb2gmf -L/usr/lpp/db2_05_00/lib |
| Compile and Link Options for bldmfcob |
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The script file contains the following compile options:
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The script file contains the following link options:
Refer to your compiler documentation for additional compiler
options.
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To build the sample program updat from the source file updat.sqb, enter:
bldmfcob updat
The result is an executable file updat. You can run the executable file against the sample database by entering:
updat
| Note: | To build Micro Focus COBOL applications that do not contain embedded SQL, you can use the script file bldmfapi. It contains the same compile and link options as bldmfcob, but does not connect, prep, bind, or disconnect from the sample database. It is used to compile and link DB2 API sample programs written in COBOL. |
| Note: | Some of the more recent versions of the Micro Focus COBOL compiler, used on
an AIX Version 4 platform, cannot be used to create a statically-linked stored
procedure. As such, the makefile and script file, bldmfcobs,
have been adapted to allow for the creation of a dynamically-linked stored
procedure.
In order for a remote client application to successfully call this dynamically-linked stored procedure, it is necessary for a Micro Focus COBOL routine, cobinit(), to be called on the server where the stored procedure resides just before the stored procedure is executed. A wrapper program which accomplishes this is created during the execution of the makefile, or the script file bldmfcobs. It is then linked with the stored procedure code to form the stored procedure shared library. Due to the use of this wrapper program, in order for a client application to call a stored procedure named x, it must call x_wrap instead of x. The details of the wrapper program are explained later in this section. |
The script file, bldmfcobs, in sqllib/samples/cobol_mf, contains the commands to build a stored procedure. The script file compiles the stored procedure into a shared library on the server that can be called by a client application.
The first parameter, $1, specifies the name of your source file. The second parameter, $2, specifies the name of the database to which you want to connect. Parameter $3 specifies the user ID for the database, and $4 specifies the password. Only the first parameter, the source file name, is required. Database name, user ID, and password are optional. If no database name is supplied, the program uses the default sample database.
The script file uses the source file name, $1, for the shared library name.
#! /bin/ksh
# bldmfcobs script file
# Build sample COBOL stored procedure
# Usage: bldmfcobs <stored_proc_name> [ <db_name> [ <userid> <password> ]]
# Connect to a database.
if (($# < 2))
then
db2 connect to sample
elif (($# < 3))
then
db2 connect to $2
else
db2 connect to $2 user $3 using $4
fi
# Precompile the program.
db2 prep $1.sqb bindfile
# Bind the program to the database.
db2 bind $1.bnd
# Disconnect from the database.
db2 connect reset
# Set COBCPY to include the DB2 COPY files directory.
export COBCPY=/usr/lpp/db2_05_00/include/cobol_mf:$COBCPY
# Compile the checkerr.cbl error checking utility.
cob -c -x checkerr.cbl
# Compile the program.
cob -c -x $1.cbl
# Create the wrapper program for the stored procedure.
wrpmfcobs $1
# Link the program using the export file ${1}_wrap.exp,
# creating a shared library called $1 with the main
# entry point ${1}_wrap.
cob -x -o $1 ${1}_wrap.c $1.o -Q -bE:${1}_wrap.exp -Q "-e $1" \
-Q -bI:/usr/lpp/db2_05_00/lib/db2g.imp -ldb2gmf -L/usr/lpp/db2_05_00/lib
# Copy the shared library to the DB2 instance sqllib/function subdirectory.
# Note: this assumes the user has write permission to this directory.
eval "H=~$DB2INSTANCE"
rm $H/sqllib/function/$1
cp $1 $H/sqllib/function
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| Compile and Link Options for bldmfcobs |
|---|
|
The script file contains the following compile options:
|
|
The script file contains the following link options:
Refer to your compiler documentation for additional compiler
options.
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The wrapper program, wrpmfcobs, causes the Micro Focus COBOL routine, cobinit(), to be called right before the stored procedure is executed. Its contents are shown below.
#! /bin/ksh
# wrpmfcobs script file
# Create the wrapper program for sample COBOL stored procedure
# Usage: wrpmfcobs <stored_proc_name>
# Note: With the wrapper program, the client application must call x_wrap
# instead of x, where x is the original name of the stored procedure.
# Create the wrapper program for the stored procedure.
cat << WRAPPER_CODE > ${1}_wrap.c
#include <stdio.h>
void cobinit(void);
int $1(void *p0, void *p1, void *p2, void *p3);
int main(void)
{
return 0;
}
int ${1}_wrap(void *p0, void *p1, void *p2, void *p3)
{
cobinit();
return $1(p0, p1, p2, p3);
}
WRAPPER_CODE
# Create the export file for the wrapper program
echo $1_wrap > ${1}_wrap.exp
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To build the sample program outsrv from the source file outsrv.sqb, enter:
bldmfcobs outsrv
The script file copies the stored procedure to the server in the path sqllib/function to indicate that the stored procedure is fenced. If you want the stored procedure to be unfenced, you must move it to the sqllib/function/unfenced directory. These paths are in the home directory of the DB2 instance.
| Note: | An unfenced stored procedure or UDF runs in the same address space as the database manager and results in increased performance when compared to a fenced stored procedure or UDF, which runs in an address space isolated from the database manager. With unfenced stored procedures or UDFs there is a danger that user code could accidentally or maliciously damage the database control structures. Therefore, you should only run unfenced stored procedures or UDFs when you need to maximize the performance benefits. Ensure these programs are thoroughly tested before running them as unfenced. Refer to the Embedded SQL Programming Guide for more information about fenced and unfenced stored procedures. |
If necessary, set the file mode for the stored procedure so the DB2 instance can run it.
Once you build the stored procedure outsrv, you can build the client application outcli that calls the stored procedure. You can build outcli using the bldcob script file. Refer to "Micro Focus COBOL" for details.
To call the stored procedure, run the sample client application by entering:
outcli remote_database userid password
where
The client application passes a variable to the server program outsrv, which gives it a value and then returns the variable to the client application.
When you develop a stored procedure, exit the stored procedure using the following statement:
move SQLZ-HOLD-PROC to return-code.
With this statement, the stored procedure returns correctly to the client application. This is especially important when the stored procedure is called by a local COBOL client application.