Sponsored Content
Top Forums UNIX for Advanced & Expert Users Detecting unused variables... Post 302975409 by wisecracker on Sunday 12th of June 2016 08:50:43 AM
Old 06-12-2016
(Bringing it back to the title.)

Hi Don et al...

Since you guys have given valid crticism of AudioScope.sh it has made me look more deeply into posix compliance, so......

I typed this directly into ShellCheck and got the bizarre results below.
It means I have to check absolutelty everything from variable constructs to printing to 'STDOUT'.
It looks like ShellCheck successfully finds any variables that seem unused; however...
Ignore the printf STDOUT printing _errors_ that could be produced as I am now fully aware of those...
Code:
#!/bin/sh
x='A string.'
y='Another string.'
text='\x1B[0m'$y' '$x'These variables look OK!'
texts="1x1B[0m"$y' '$x"These variables look OK too!."
txt='\x1B[0m'$y" "$x'These variables look OK also!'
txts="\x1B[0m"$y" "$x"This is bizarre, why the inverted commas error?"

Code:
$ shellcheck myscript
 
Line 4:
text='\x1B[0m'$y' '$x'These variables look OK!'
^-- SC2034: text appears unused. Verify it or export it.
 
Line 5:
texts="1x1B[0m"$y' '$x"These variables look OK too!."
^-- SC2034: texts appears unused. Verify it or export it.
 
Line 6:
txt='\x1B[0m'$y" "$x'These variables look OK also!'
^-- SC2034: txt appears unused. Verify it or export it.
 
Line 7:
txts="\x1B[0m"$y" "$x"This is bizarre, why the inverted commas error?"
^-- SC2034: txts appears unused. Verify it or export it.
              ^-- SC2027: The surrounding quotes actually unquote this. Remove or escape them.
                   ^-- SC2027: The surrounding quotes actually unquote this. Remove or escape them.

$

I have made a rod for my own back here...

Thanks to Don all for your input...
 

9 More Discussions You Might Find Interesting

1. UNIX for Dummies Questions & Answers

How do I get the unused space?

One of my Solaris 8 machines hd was about to die. So I used g4u to create an image of the 9gb drive and I put it in a 36gb drive. That solved my dieing hd problem. But.... How do I get my machine to see the unused 27gb of space? Any help would be greatly appreciated. (1 Reply)
Discussion started by: Spyzic
1 Replies

2. AIX

unused storage on AIX 4.3

Hi, How do I query for unused partition in AIX 4.3 with DAS and SAA storage? I know most unix administrator don't put all the capacity on the system at once. thanks, vene (1 Reply)
Discussion started by: venerayan
1 Replies

3. UNIX for Dummies Questions & Answers

delete the unused file

Hi All, Can you please let me know how to delete any files that have not been accessed in the past 28 days in a directory. Thanks, Arun (3 Replies)
Discussion started by: arunkumar_mca
3 Replies

4. AIX

how to clean Unused semaphore??

How can i clean up my unused semaphore??? (4 Replies)
Discussion started by: abhishek27
4 Replies

5. HP-UX

HP-UX using unused HDD space

Hello, I have a system with HP-UX 11.23 installed on it. There are ~36GB of unused space on the HDD. I did a very basic installation, and it created the usual volume group /dev/vg00. When I look at the output of ioscan -funC disk, I see this (and more, but irrelevant to this post): disk ... (1 Reply)
Discussion started by: goon12
1 Replies

6. Solaris

unused disk space

i Have alloted 20G in my vmware for solaris 10, upon installation, and some distribution of disk space to /,/opt,swap i just use 19G. Can i still use the 1G? How? how to see the 1G? that i did not use? how can i use it? appreciate your responce (17 Replies)
Discussion started by: kenshinhimura
17 Replies

7. AIX

Temporarily disabling unused ethernet adapter

Hi, In our AIX 5.2 server , we have one unused ethernet adapter which doesn't have cable connection . For this interface , we are getting alerts in errpt . Could you suggesthow to stop this alert ? And sametime i would like to keep this device in ODM . Is there... (1 Reply)
Discussion started by: sekarsamy
1 Replies

8. Programming

What Unix do with unused shared memory?

Hello, When creating shared memory in C, should be remove shared memory with shmctl function when don't need it. If it didn't remove, occupied shared memory stay and remain. If we create shared memory repeatedly without removing unusable shared memory, /dev/shm will full. Does Unix or... (1 Reply)
Discussion started by: pronetin
1 Replies

9. Solaris

Solaris 10: how to disable an unused HBA card

Dear all, I have a new Oracle Blade X4-2B server, running Solaris 10. The server comes with a HBA card that will not be used now. It has not fibers connected to it. As a consequence, its leds never stop flashing. My question is: how to disable this HBA card, without removing it physically... (2 Replies)
Discussion started by: Gus1971
2 Replies
EXPORT(1P)						     POSIX Programmer's Manual							EXPORT(1P)

PROLOG
This manual page is part of the POSIX Programmer's Manual. The Linux implementation of this interface may differ (consult the correspond- ing Linux manual page for details of Linux behavior), or the interface may not be implemented on Linux. NAME
export - set the export attribute for variables SYNOPSIS
export name[=word]... export -p DESCRIPTION
The shell shall give the export attribute to the variables corresponding to the specified names, which shall cause them to be in the envi- ronment of subsequently executed commands. If the name of a variable is followed by = word, then the value of that variable shall be set to word. The export special built-in shall support the Base Definitions volume of IEEE Std 1003.1-2001, Section 12.2, Utility Syntax Guidelines. When -p is specified, export shall write to the standard output the names and values of all exported variables, in the following format: "export %s=%s ", <name>, <value> if name is set, and: "export %s ", <name> if name is unset. The shell shall format the output, including the proper use of quoting, so that it is suitable for reinput to the shell as commands that achieve the same exporting results, except: 1. Read-only variables with values cannot be reset. 2. Variables that were unset at the time they were output need not be reset to the unset state if a value is assigned to the variable between the time the state was saved and the time at which the saved output is reinput to the shell. When no arguments are given, the results are unspecified. OPTIONS
See the DESCRIPTION. OPERANDS
See the DESCRIPTION. STDIN
Not used. INPUT FILES
None. ENVIRONMENT VARIABLES
None. ASYNCHRONOUS EVENTS
Default. STDOUT
See the DESCRIPTION. STDERR
The standard error shall be used only for diagnostic messages. OUTPUT FILES
None. EXTENDED DESCRIPTION
None. EXIT STATUS
Zero. CONSEQUENCES OF ERRORS
Default. The following sections are informative. APPLICATION USAGE
None. EXAMPLES
Export PWD and HOME variables: export PWD HOME Set and export the PATH variable: export PATH=/local/bin:$PATH Save and restore all exported variables: export -p > temp-fileunset a lot of variables... processing. temp-file RATIONALE
Some historical shells use the no-argument case as the functional equivalent of what is required here with -p. This feature was left unspecified because it is not historical practice in all shells, and some scripts may rely on the now-unspecified results on their imple- mentations. Attempts to specify the -p output as the default case were unsuccessful in achieving consensus. The -p option was added to allow portable access to the values that can be saved and then later restored using; for example, a dot script. FUTURE DIRECTIONS
None. SEE ALSO
Special Built-In Utilities COPYRIGHT
Portions of this text are reprinted and reproduced in electronic form from IEEE Std 1003.1, 2003 Edition, Standard for Information Technol- ogy -- Portable Operating System Interface (POSIX), The Open Group Base Specifications Issue 6, Copyright (C) 2001-2003 by the Institute of Electrical and Electronics Engineers, Inc and The Open Group. In the event of any discrepancy between this version and the original IEEE and The Open Group Standard, the original IEEE and The Open Group Standard is the referee document. The original Standard can be obtained online at http://www.opengroup.org/unix/online.html . IEEE
/The Open Group 2003 EXPORT(1P)
All times are GMT -4. The time now is 10:15 PM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy