The script file, bldcc, in sqllib/samples/c, contains the commands to build a sample C 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. The third parameter, $3, specifies the user ID for the database, and $4 specifies the password. Only the first parameter, the source file name, is required. Database name, user ID, and password are optional. If no database name is supplied, the program uses the default sample database.
#! /bin/ksh # bldcc script file # Builds a sample C program containing embedded SQL # Usage: bldcc <prog_name> [ <db_name> [ <userid> <password> ]] # Connect to a database. if (($# < 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.sqc bindfile # Bind the program to the database. db2 bind $1.bnd # Disconnect from the database. db2 connect reset # Compile the util.c error-checking utility. cc -Aa +DAportable +e -I/opt/IBMdb2/V5.0/include -c util.c # Compile the program. cc -Aa +DAportable +e -I/opt/IBMdb2/V5.0/include -c $1.c # Link the program. cc +DAportable -o $1 $1.o util.o -L/opt/IBMdb2/V5.0/lib -ldb2 -lhppa |
| Compile and Link Options for bldcc |
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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.sqc, enter:
bldcc updat
The result is an executable file updat. You can run the executable file against the sample database by entering:
updat
| Note: | To build C applications that do not contain embedded SQL, you can use the script file bldccapi. It contains the same compile and link options as bldcc, but does not connect, prep, bind, or disconnect from the sample database. It is used to compile and link the DB2 API sample programs written in C. |
The script file bldccsrv, in sqllib/samples/c, contains the commands to build a C stored procedure. The script file compiles the stored procedure into a shared library 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. The third 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, $1, for the shared library name.
#! /bin/ksh # bldccsrv script file # Build C stored procedure. # Usage: bldccsrv <prog_name> [ <db_name> [ <userid> <password> ]] # Connect to a database. if (($# < 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.sqc bindfile # Bind the program to the database. db2 bind $1.bnd # Disconnect from the database. db2 connect reset # Compile the program. cc +u1 +Z -Aa +DAportable +e -I/opt/IBMdb2/V5.0/include -c $1.c # Link the program to create a shared library ld -b -o $1 $1.o -L/opt/IBMdb2/V5.0/lib -ldb2 # Copy the shared library to the sqllib/function subdirectory of the DB2 instance. # Note: this assumes the user has write permission to this directory. eval "H=~$DB2INSTANCE" cp $1 $H/sqllib/function |
| Compile and Link Options for bldccsrv |
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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.
|
To build the sample program outsrv from the source file outsrv.sqc, enter:
bldccsrv 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 bldcc script file. Refer to "HP-UX C" 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.
The script file bldccudf, in sqllib/samples/c, contains the commands to build a UDF. UDFs are compiled like stored procedures, but you do not need to connect to a database or precompile and bind the program.
| Note: | A UDF does not contain embedded SQL statements. Rather, the application that uses the UDF contains the statements, such as calludf. |
The first parameter, $1, specifies the name of your source file. The script file also uses this source file name for the shared library name.
#! /bin/ksh # bldccudf script file # Builds sample c UDF library. # Usage: bldccudf <prog_name> # Compile the program. cc +u1 +Z -Aa +DAportable +e -I/opt/IBMdb2/V5.0/include -c $1.c # Link the program and create a shared library. ld -b -o $1 $1.o -L/opt/IBMdb2/V5.0/lib -ldb2 -ldb2apie # Copy the shared library to the sqllib/function subdirectory of the DB2 instance. # Note: this assumes the user has write permission to this directory. eval "H=~$DB2INSTANCE" cp $1 $H/sqllib/function |
| Compile and Link Options for bldccudf |
|---|
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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.
|
To build the user-defined function program udf from the source file udf.c, enter:
bldccudf udf
The script file copies the UDF to the server in the path sqllib/function to indicate that the UDF is fenced. If you want the UDF 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 UDF or stored procedure runs in the same address space as the database manager and results in increased performance when compared to a fenced UDF or stored procedure, which runs in an address space isolated from the database manager. With unfenced UDFs or stored procedures there is a danger that user code could accidentally or maliciously damage the database control structures. Therefore, you should only run unfenced UDFs or stored procedures 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 UDFs. |
If necessary, set the file mode for the UDF so the DB2 instance can run it.
Once you build udf, you can build the client application, calludf, that calls it. You can build calludf using the bldcc script file. Refer to "HP-UX C" for details.
To call the UDF, run the sample calling application by entering:
calludf
The calling application calls functions from the udf library.
| Note: | Multi-threaded applications are not supported by DB2 on version 10 of the HP-UX operating system. HP-UX version 11 provides a posix thread library and a DCE thread library. Multi-threaded applications using the posix thread library are supported by DB2 on HP-UX version 11. |
Multi-threaded applications on HP-UX version 11 need to have _REENTRANT defined for their compilation. The HP-UX documentation recommends compiling with -D_POSIX_C_SOURCE=199506L. This will also ensure _REENTRANT is defined. Applications also need to be linked with -lpthread.
The makefile in sqllib/samples/c contains the commands to build a sample C multi-threaded program. The makefile defines variables for the compile and link options. When the make command is run the variables are replaced by their values, as in the following example where the makefile is used to compile the thdsrver program:
cc -o thdsrver thdsrver.c -Aa +DAportable +e -I/home/db2inst/sqllib/include -D_POSIX_C_SOURCE=199506L -L/home/db2inst/sqllib/lib -ldb2 -lhppa -lpthread |
where /home/db2inst is the DB2 instance directory.
For definitions of the non-multi-threaded options, please see "Compile and Link options for bldcc" in "HP-UX C".
To build the sample program, thdsrver, enter:
make thdsrver
The result is an executable file, thdsrver. To run the executable file against the sample database, enter:
thdsrver