Open System Services Shell and Utilities Reference Manual (G06.29+, H06.08+, J06.03+)

gtacl(1) OSS Shell and Utilities Reference Manual
Use in Shell Scripts
Guardian processes typically open a Guardian environment disk file for output by requesting pro-
tected or exclusive access. This practice can conflict with use of exclusion mode by an OSS pro-
cess.
For example:
gtacl -p FUP ’INFO *’
fails if it is invoked from an OSS shell script and the output of the script is redirected to a Guar-
dian disk file. Because the output file can be opened from the Guardian environment, gtacl does
not filter the output. However, because the output file is still open by the shell process executing
the script, FUP cannot open the file for exclusive access and terminates abnormally.
To avoid this problem when gtacl is used within a shell script, use the -i or +i option to force
input/output filtering, as follows:
gtacl -i -p FUP ’INFO *’
OSS Environment Variables
The following OSS environment variables affect the execution of the gtacl command.
PMSEARCHLIST
If this variable is defined, gtacl uses the value if necessary to
resolve a Guardian file identifier to find the program specified
with the -p or -prog option. The value can be one or more of the
following:
• a list of Guardian subvolume names in Guardian exter-
nal file name format, separated by spaces. These subvo-
lumes are searched when resolving a Guardian file
identifier to find the program specified with the -p or
-prog option.
• the TACL command interpreter #DEFAULTS built-in
variable.
• the TACL command interpreter identifiers
#DEFAULTS/CURRENT/ or #DEFAULTS/SAVED/.
If this variable is not defined, gtacl uses the /G/system/system
subvolume to resolve a relative filename.
PWD This variable must resolve to a valid Guardian filesystem subvo-
lume name. If the value for this variable appears to be an OSS
pathname outside of the /G directory, gtacl ignores the value.
If this variable is correctly specified, gtacl interprets the value as
a Guardian volume and subvolume name. The gtacl process
passes the value to the child process in the default volume and
subvolume part of the Guardian environment Startup message.
If this variable is not defined or is incorrectly specified, then
gtacl uses the inherited default volume and subvolume names
from the =_DEFAULTS DEFINE for the Guardian environment
Startup message.
Unless the -s option is used, OSS environment variables are converted into
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