Create a subprocess.
Syntax
SPAWN [command]
Qualifiers Defaults
/INPUT=in-file-spec None
/LOGICAL_NAMES /LOGICAL_NAMES
/OUTPUT=out-file-spec None
/PROCESS=name None
/SYMBOLS /SYMBOLS
/WAIT /WAIT
1 – Restrictions
Cannot be used from a captive account.
2 – Parameters
command
Optional parameter specifying the command string for the
subprocess to execute. After the command completes, the
subprocess terminates and control is returned to the parent
process.
3 – Description
The SPAWN command can be used to either issue a single DCL
command from within PMDF QM or to leave PMDF QM temporarily, do
other work (e.g., type out a file, generate a directory listing,
etc.), and then return to PMDF QM.
By default, the context of the current process is copied to the
subprocess. This behavior can be controlled with the /LOGICAL_
NAMES and /SYMBOLS qualifiers.
4 – Qualifiers
4.1 /INPUT
/INPUT=in-file-spec
Specifies an input command file from which the subprocess is to
draw command input. Once command processing is completed, the
subprocess terminates. When you specify both a command string and
input file, then the command string is first processed and then
the commands from the input file.
4.2 /LOGICAL_NAMES
/LOGICAL_NAMES (default)
/NOLOGICAL_NAMES
The /LOGICAL_NAMES qualifier specifies that the logical names
of the parent process are to be copied to the subprocess. This
is the default behavior. Specify /NOLOGICAL_NAMES to prevent the
subprocess from inheriting the logical name definitions of its
parent.
4.3 /OUTPUT
/OUTPUT=out-file-spec
Specifies the output file to which the output of the subprocess
is to be directed. If the /OUTPUT qualifier is omitted, then
subprocess output is directed to the current SYS$OUTPUT device
(generally, your terminal).
4.4 /PROCESS
/PROCESS=name
Specifies the process name to associate with the subprocess.
If not specified, a default name of the form USERNAME_n, where
"USERNAME" is your username, is used.
4.5 /SYMBOLS
/SYMBOLS (default)
/NOSYMBOLS
The /SYMBOLS qualifier specifies that the DCL symbol definitions
of the parent process are to be copied to the subprocess. This
is the default behavior. Specify /NOSYMBOLS to prevent the
subprocess from inheriting the symbol definitions of its parent.
4.6 /WAIT
/WAIT (default)
/NOWAIT
By default, your current (parent) process will wait until the
subprocess has finished its processing and terminated. This
default behavior is explicitly selected with the /WAIT qualifier.
The /NOWAIT qualifier allows you to continue working from your
current process while the subprocess is running. When you specify
/NOWAIT, you should also specify the /OUTPUT qualifier so as to
prevent the subprocess output from appearing on your terminal
screen.
5 – Examples
1.qm.user> SPAWN DIRECTORY/SIZE=ALL A.TXT
Directory D1:[BOB]
A.TXT;10 125/126
A.TXT;9 124/126
A.TXT;8 124/126
Total of 3 files, 373/378.
qm.user> SPAWN PURGE/LOG A.TXT
%PURGE-I-FILPURG, D1:[BOB]A.TXT;9 deleted (126 blocks)
%PURGE-I-FILPURG, D1:[BOB]A.TXT;8 deleted (126 blocks)
%PURGE-I-TOTAL, 2 files deleted (252 blocks)
qm.user>
In this example, the SPAWN command is used to obtain a
directory listing of the files A.TXT, and then to purge back
old versions of that file. The ability to do this is useful
when you find that you have insufficient disk quota to create
and edit a mail message you want to send.
2.qm.user> SPAWN
.
.
.
$ LOGOUT
Process BOB_1 logged out at 23-AUG-2012 12:12:51.42
qm.user>
In this example a SPAWN command with no command string is
issued. This places you into the subprocess where you can issue
DCL commands and perform other processing. When you are done
with the subprocess and ready to return to PMDF QM, use the
LOGOUT or EOJ command.