I want to save the output of a program to a variable.
I use the following approach ,but fail.
$ PIPE RUN TEST | DEFINE/JOB VALUE #SYS$PIPE
$ x = f$logical("VALUE")
I got an error:%DCL-W-MAXPARM, too many parameters - reenter command with fewer parameters
\WORLD\
reference :
How to assign the output of a program to a variable in a DCL com script on VMS?
The usual way to do this is to write the output to a file and read from the file and put that into a DCL symbol (or logical). Although not obvious, you can do this with the PIPE command was well:
$ pipe r 2words
hello world
$ pipe r 2words |(read sys$pipe line ; line=""""+line+"""" ; def/job value &line )
$ sh log value
"VALUE" = "hello world" (LNM$JOB_85AB4440)
$
IF you are able to change the program, add some code to it to write the required values into symbols or logicals (see LIB$ routines)
If you can modify the program, using LIB$SET_SYMBOL in the program defines a DCL symbol (what you are calling a variable) for DCL. That's the cleanest way to do this. If it really needs to be a logical, then there are system calls that define logicals.
Related
I'm trying to run a series of shell commands with Perl6 to the variable $cmd, which look like
databricks jobs run-now --job-id 35 --notebook-params '{"directory": "s3://bucket", "output": "s3://bucket/extension", "sampleID_to_canonical_id_map": "s3://somefile.csv"}'
Splitting the command by everything after notebook-params
my $cmd0 = 'databricks jobs run-now --job-id 35 --notebook-params ';
my $args = "'{\"directory\": \"$in-dir\", \"output\": \"$out-dir\",
\"sampleID_to_canonical_id_map\": \"$map\"}'"; my $run = run $cmd0,
$args, :err, :out;
Fails. No answer given either by Databricks or the shell. Stdout and stderr are empty.
Splitting the entire command by white space
my #cmd = $cmd.split(/\s+/);
my $run = run $cmd, :err, :out
Error: Got unexpected extra arguments ("s3://bucket", "output":
"s3://bucket/extension",
"sampleID_to_canonical_id_map":
"s3://somefile.csv"}'
Submitting the command as a string
my $cmd = "$cmd0\"$in-dir\", \"output\": \"$out-dir\", \"sampleID_to_canonical_id_map\": \"$map\"}'";
again, stdout and stderr are empty. Exit code 1.
this is something about how run can only accept arrays, and not strings (I'm curious why)
If I copy and paste the command that was given to Perl6's run, it works when given from the shell. It doesn't work when given through perl6. This isn't good, because I have to execute this command hundreds of times.
Perhaps Perl6's shell https://docs.perl6.org/routine/shell would be better? I didn't use that, because the manual suggests that run is safer. I want to capture both stdout and stderr inside a Proc class
EDIT: I've gotten this running with shell but have encountered other problems not related to what I originally posted. I'm not sure if this qualifies as being answered then. I just decided to use backticks with perl5. Yes, backticks are deprecated, but they get the job done.
I'm trying to run a series of shell commands
To run shell commands, call the shell routine. It passes the positional argument you provide it, coerced to a single string, to the shell of the system you're running the P6 program on.
For running commands without involving a shell, call the run routine. The first positional argument is coerced to a string and passed to the operating system as the filename of the program you want run. The remaining arguments are concatenated together with a space in between each argument to form a single string that is passed as a command line to the program being run.
my $cmd0 = 'databricks jobs run-now --job-id 35 --notebook-params ';
That's wrong for both shell and run:
shell only accepts one argument and $cmd0 is incomplete.
The first argument for run is a string interpreted by the OS as the filename of a program to be run and $cmd0 isn't a filename.
So in both cases you'll get either no result or nonsense results.
Your other two experiments are also invalid in their own ways as you discovered.
this is something about how run can only accept arrays, and not strings (I'm curious why)
run can accept a single argument. It would be passed to the OS as the name of the program to be run.
It can accept two arguments. The first would be the program name, the second the command line passed to the program.
It can accept three or more arguments. The first would be the program name, the rest would be concatenated to form the command line passed to the program. (There are cases where this is more convenient coding wise than the two argument form.)
run can also accept a single array. The first element would the program name and the rest the command line passed to it. (There are cases where this is more convenient.)
I just decided to use backticks with perl5. Yes, backticks are deprecated, but they get the job done.
Backticks are subject to code injection and shell interpolation attacks and errors. But yes, if they work, they work.
P6 has direct equivalents of most P5 features. This includes backticks. P6 has two variants:
The safer P6 alternative to backticks is qx. The qx quoting construct calls the shell but does not interpolate P6 variables so it has the same sort of level of danger as using shell with a single quoted string.
The qqx variant is the direct equivalent of P5 backticks or using shell with a double quoted string so it suffers from the same security dangers.
Two mistakes:
the simplistic split cuts up the last, single parameter into multiple arguments
you are passing $cmd to run, not #cmd
use strict;
my #cmd = ('/tmp/dummy.sh', '--param1', 'param2 with spaces');
my $run = run #cmd, :err, :out;
print(#cmd ~ "\n");
print("EXIT_CODE:\t" ~ $run.exitcode ~ "\n");
print("STDOUT:\t" ~ $run.out.slurp ~ "\n");
print("STDERR:\t" ~ $run.err.slurp ~ "\n");
output:
$ cat /tmp/dummy.sh
#!/bin/bash
echo "prog: '$0'"
echo "arg1: '$1'"
echo "arg2: '$2'"
exit 0
$ perl6 dummy.pl
/tmp/dummy.sh --param1 param2 with spaces
EXIT_CODE: 0
STDOUT: prog: '/tmp/dummy.sh'
arg1: '--param1'
arg2: 'param2 with spaces'
STDERR:
If you can avoid generating $cmd as single string, I would generate it into #cmd directly. Otherwise you'll have to implement complex split operation that handles quoting.
Expect script query:
In one of my expect script I have to pick keyword from output of send command and store in a file, could some one help me.
send "me\n"
output :
EM/X Nmis Ssh Session/2; Userid =
Impact = ; Scope = ; CustomerId = 0
Here I want to pick keyword : Nmis Ssh Session/2
and my target is to create new command in expect script is :
send "set Nmis Ssh Session/2 \n"
so this value : Nmis Ssh Session/2 should store in a variable. Could some one help me.
I'm not quite sure exactly what information is produced by which side, but maybe something like this will do:
expect -re {EM/X ([^;]+);}
set theVariable $expect_out(1,string)
The key is that we use the -re option to pass a regular expression to the expect command. That makes the text that matches what is in the parentheses (a sequence of non-semicolon characters) be stored in the variable expect_out(1,string) (there are many other things stored in the expect_out array; see the documentation). Copying it from there to a named variable for the purpose of storage and further manipulation is trivial.
I do not know if the RE is the right one; there's something of an art in choosing the right one, and it takes quite a lot of knowledge about what the possible output of the other side could be.
We are currently using sed to filter output of regression runs. Sometimes we have a filter that looks like this:
/copyright/,/end copyright/d
If that end copyright is ever missing, the rest of the file is deleted. I'm wondering if there's some way to generate an error for this? awk would also be okay to use. I don't really want to add code that reads the file line by line and issues an error if it hits EOF.
here's a string
copyright
2016 jan 15
end copyright
date 2016 jan 5 time 15:36
last one
I'd like to get an error if end copyright is missing. The real filter also would replace the date line with DATE, so it's more that just ripping out the copyright.
You can persuade sed to generate an error if you reach end of input (i.e. see address $) between your start and end, but it won't be a very helpful message:
/copyright/,/end copyright/{
$s//\1/ # here
d
}
This will error if end copyright is missing or on the last line, with an exit status of 1 and the helpful message:
sed: -e expression #1, char 0: invalid reference \1 on `s' command's RHS
If you're using this in a makefile, you might want to echo a helpful message first, or (better) to wrap this in something that catches the error and produces a more useful one.
I tested this with GNU sed; though if you are using GNU sed, you could more easily use its useful extension:
q [EXIT-CODE]
This command only accepts a single address.
Exit 'sed' without processing any more commands or input. Note
that the current pattern space is printed if auto-print is not
disabled with the -n options. The ability to return an exit code
from the 'sed' script is a GNU 'sed' extension.
Q [EXIT-CODE]
This command only accepts a single address.
This command is the same as 'q', but will not print the contents of
pattern space. Like 'q', it provides the ability to return an exit
code to the caller.
So you could simply write
/copyright/,/end copyright/{
$Q 42
d
}
Never use range expressions /start/,/end/ as they make trivial code very slightly briefer but require a complete rewrite or duplicate conditions when you have the tiniest requirements change. Always use a flag instead. Note that since sed doesn't support variables, it doesn't support flag variables, and so you shouldn't be using sed you should be using awk instead.
In this case your original code would be:
awk '/copyright/{f=1} !f; /end copyright/{f=0}' file
And your modified code would be:
awk '/copyright/{f=1} !f; /end copyright/{f=0} END{if (f) print "Missing end copyright"}' file
The above is obviously untested since you didn't provide any sample input/output we could test a potential solution against.
With sed you can build a loop:
sed -e '/copyright/{:a;/end copyright/d;N;ba;};' file
:a defines the label "a"
/copyright end/d deletes the pattern space, only when "end copyright" matches
N appends the next line to the pattern space
ba jumps to the label "a"
Note that d ends the loop.
In this way you can avoid to delete the text until the end.
If you don't want the text to be displayed at all and prefer an error message when a "copyright" block stays unclosed, you obviously need to wait the end of the file. You can do it with sed too storing all the lines in the buffer space until the end:
sed -n -e '/copyright/{:a;/end copyright/d;${c\ERROR MESSAGE
;};N;ba;};H;${g;p};' file
H appends the current line to the buffer space
g put the content of the buffer space to the pattern space
The file content is only displayed once the last line reached with ${g;p} otherwise when the closing "end copyright" is missing, the current line is changed in the error message with ${c\ERROR MESSAGE\n;} inside the loop.
This way you can test what returns sed before redirecting it to whatever you want.
Im having an issue writing a DCL in OpenVMS in that I need the DCL to call a command and capture its output (but not output the output to the screen) Later on in the DCL I then need to print that output I stored.
Heres an example:
ICE SET FASTER !This command sets my environment to the "Faster" environment.
The above command outputs this if executed directly in OpenVMS:
Initialising TEST Environment to FASTER
--------------------------------------------------------------------------------
Using Test Search rules FASTER
Using Test Search rules FASTER
--------------------------------------------------------------------------------
dcl>
So I created a DCL in an attempt to wrap this output in order to display a more simplified output. Heres my code so far:
!************************************************************************
$ !* Wrapper for setting ICE account. Outputs Environment
$ !************************************************************************
$ on error then goto ABORT_PROCESS
$ICE_DCL_MAIN:
$ ice set 'P1'
$ ICE SHOW
$ EXIT
$ABORT_PROCESS:
$ say "Error ICING to: " + P1
$ EXIT 2
[End of file]
In the lines above ICE SET 'P1' is setting the ice environment, but I dont want this output to be echoed to VMS. But what I do want is to write the output of $ICE SHOW into a variable and then echo that out later on in the DCL (most of which ive omitted for simplification purposes)
So what should be outputted should be:
current Test Environment is DISK$DEVELOPERS:[FASTER.DEVELOP]
Instead of:
Initialising TEST Environment to FASTER
--------------------------------------------------------------------------------
Using Test Search rules FASTER
Using Test Search rules FASTER
--------------------------------------------------------------------------------
current Test Environment is DISK$DEVELOPERS:[FASTER.DEVELOP]
Ive had a look through the manual and im getting a bit confused so I figured I tried here. Id appreciate any pointers. Thanks.
EDIT
Here is what ive come up with after the comments, the problem im having is when I connect to VMS using an emulator such as SecureCRT the correct output is echoed. But when I run the DCL via my SSH2 library in .NET it doesnt output anything. I guess thats because it closes the SYS$OUTPUT stream temporarily or something?
$ !************************************************************************
$ !* Wrapper for setting ICE account. Outputs Environment
$ !************************************************************************
$ on error then goto ABORT_PROCESS
$ICE_DCL_MAIN:
$ DEFINE SYS$OUTPUT NL:
$ ice set 'P1'
$ DEASSIGN SYS$OUTPUT
$ ice show
$ EXIT
$ABORT_PROCESS:
$ say "Error ICING to: " + P1
$ EXIT 2
[End of file]
EDIT 2
So I guess really I need to clarify what im trying to do here. Blocking the output doesnt so matter so much, im merely trying to capture it into a Symbol for example.
So in C# for example you can have a method that returns a string. So you'd have string myResult = vms.ICETo("FASTER"); and it would return that and store it in the variable.
I guess im looking for a similar thing in VMS so that once ive iced to the environment I can call:
$ environment == $ICE SHOW
But I of course get errors with that statement
The command $ assign/user_mode Thing Sys$Output will cause output to be redirected to Thing until you $ deassign/user_mode Sys$Output or next executable image exits. An assignment without the /USER_MODE qualifier will persist until deassigned.
Thing can be a logical name, a file specification (LOG.TXT) or the null device (NLA0:) if you simply want to flush the output.
When a command procedure is executed the output can be redirected using an /OUTPUT qualifier, e.g. $ #FOO/output=LOG.TXT.
And then there is piping ... .
You can redirect the output to a temp file and then print its content later:
$ pipe write sys$output "hi" > tmp.tmp
$ ty tmp.tmp
VMS is not Unix, DCL is not Bash: you can not easily set a DCL symbol from the output of a command.
Your ICE SHOW prints one line, correct? The first word is always "current", correct?
So you can create a hack.
First let me fake your ICE command:
$ create ice.com
$ write sys$output "current Test Environment is DISK$DEVELOPERS:[FASTER.DEVELOP]"
^Z
$
and I define a dcl$path pointing to the directory where this command procedure is
so that I can use/fake the command ICE
$ define dcl$path sys$disk[]
$ ice show
current Test Environment is DISK$DEVELOPERS:[FASTER.DEVELOP]
$
Now what you need, create a command procedure which sets a job logical
$ cre deflog.com
$ def/job/nolog mylog "current''p1'"
^Z
$
And I define a command "current" to run that command procedure:
$ current="#deflog """
Yes, you need three of the double quotes at the end of the line!
And finally:
$ pipe (ice show | #sys$pipe) && mysym="''f$log("mylog")'"
$ sh symb mysym
MYSYM = "current Test Environment is DISK$DEVELOPERS:[FASTER.DEVELOP]"
$
On the other hand, I don't know what you are referring to C# and Java. Can you elaborate on that and tell us what runs where?
You can try using: DEFINE /USER SYS$OUTPUT NL:.
It works only for the next command and you dont need to deassign.
Sharing some of my experience here. I used below methods to redirect outputs to files.
Define/Assign the user output and then execute the required command/script afterwards. Output will be written to .
$define /user sys$output <file_path>
execute your command/script
OR
assign /user <file_path> sys$output
execute your command/script
deassign sys$output
To re-direct in to null device like in Unix (mentioned in above answers), you can use 'nl:' instead of
define /user sys$output nl:
or
assign /user nl: sys$output
I am new to DCL.
I want to get the out put of a command in a variable and iterate result one by one.
filePath=dir /since="time_now" [.SUBDIR]*.PNG/noheader/notrail
That's just not how we roll with DCL.
We don't do pipes, we do, but not really.
DIR/SINCE=NOW ... will not give anything by definition, since nothing exists since now.
Use /OUT to stick the directory output into a file, and then read ans parse (F$PARSE and/or F$ELEMENT and/or F$LOC)
Check out HELP OPEN; HELP READ [/END]; HELP LEXICAL
Google for examples.
More advanced DCL scripts use F$PARSE, F$SEARCH and F$FILE(file,CDT) to avoid activating images and creating temp files: $ HELP LEXICAL
Google for examples.
Check out yesterday stack-exhange entry ?! : OpenVMS - DELETE Line if TEXT like x
But if you are just starting... IMHO just skip DCL and stick to PERL
$ perl -e "for (<[.SUBDIR]*.PNG>) { next unless -M > 0.123; print; ... }"
Good luck!
Hein
top:
file = f$search("[.subdir]*.PNG")
if (file .eqs. "")then goto cont
mtime=f$file_attribute(file,"RDT")
if mtime.ges.build_start_time then -
name=f>parse(file,,,"NAME")
call CHECK "''name'"
goto top
cont:
#Hein please review this code and suggest changes