Open System Services Porting Guide (G06.29+, H06.06+, J06.03+)

OSS processes have a full set of Guardian attributes as well as OSS attributes. Most Guardian
process-management procedures can access OSS processes, and a small set of OSS
process-management functions can access Guardian processes.
The following subsections discuss these topics:
• “Process-Creation Interoperability” (page 75)
• “Process-Management Interoperability” (page 76)
• “Process-Termination Interoperability” (page 77)
Beginning with the H06.24 and J06.13 RVUs, 64-bit OSS processes can be created by Guardian
processes on TNS/E systems. For information about 64-bit OSS processes, see the 64-Bit Support
in OSS and Guardian chapter in the Open System Services Programmer's Guide.
Process-Creation Interoperability
Table 4 indicates the different ways that processes can be created using Guardian procedure calls
and OSS function calls.
Table 4 Process Creation Comparison
File Open FeatureChild ProcessParentageCallerProcedure or Function
Parent process passes
attributes to child
process
OSSOSS PIDOSSfork(), exec set,
tdm_fork(),
tdm_execve set,
tdm_spawn()
NoneGuardianAncestor or MOMGuardian or OSSPROCESS_LAUNCH_
Files to open can be
specified
OSSAncestor or MOMGuardian or OSSPROCESS_SPAWN_
fork() and exec Set of Functions
The Guardian and OSS attributes inherited by the fork() function are defined in the fork(2)
reference page either online or in the Open System Services System Calls Reference Manual. Many
Guardian attributes cannot be specified for the created child process using the fork() function.
Guardian attributes can be specified only when using HP extension functions such as tdm_fork()
and tdm_spawn(), discussed in the next subsection.
tdm_fork(), tdm_execve set, and tdm_spawn() Functions
A number of process-creation functions specific to HP are available in the OSS environment to
pass Guardian attributes from the parent process to the child process: tdm_fork(), tdm_execve(),
tdm_execvep(), and tdm_spawn(). For more information about these functions, refer to the
corresponding reference pages either online or in the Open System Services System Calls Reference
Manual.
These functions allow control of Guardian attributes in the child process. Typically, these HP functions
are used to run the child process in a processor other than the one on which the parent process is
running. In addition, these functions pass certain POSIX inheritance attributes to the child process,
give an OSS process a process name, or run the process under the control of a choice of symbolic
debuggers.
PROCESS_LAUNCH_ Procedure
All of the procedures and functions in Table 4 (page 75) can be called from the OSS environment.
However, fork(), the exec set of functions, tdm_fork(), tdm_execve(), tdm_execvep(),
and tdm_spawn() can be called only from the OSS environment. From Table 4, only
PROCESS_LAUNCH_ can be used to create a Guardian process; the others create OSS processes.
Process Interoperability 75