Login or Register to Ask a Question and Join Our Community

Sponsored Content
Full Discussion: Bash -o -v -R operators
Top Forums UNIX for Beginners Questions & Answers Bash -o -v -R operators Post 303012684 by RudiC on Wednesday 7th of February 2018 02:04:23 PM
Old 02-07-2018
You're right - those are "unary primaries" to be used in "Conditional Expressions". man bash:
Quote:
Conditional expressions are used by the [[ compound command and the test and [ builtin commands to test file attributes and perform string and arithmetic comparisons. Expressions are formed from the following unary or binary primaries.
Use like
Code:
[ -v var ]  && echo "var set" || echo Nope

or in a corresponding if construct.
Last edited by RudiC; 02-07-2018 at 03:37 PM.. Reason: better phrasing
 

9 More Discussions You Might Find Interesting

1. UNIX for Advanced & Expert Users

If with set operators

Hi guys, I'm trying to run more than one "if" condition at once. What I want is something like if ] or ] or ]; then ... I can't remember the syntax for using this or/and set operators. Can someone please assist/ jog my memory? thanks Khoom (2 Replies)
Discussion started by: Khoomfire
2 Replies

2. UNIX for Dummies Questions & Answers

Operators

I am trying to understand Does the following: {tmp+=$10} Mean take $10 and add them all up and call it tmp thanks! (2 Replies)
Discussion started by: llsmr777
2 Replies

3. Shell Programming and Scripting

And and OR Operators with If Statement.

Hi All, I have 2 variables. Result1 and Result2. I want to put a condition that if Both are True then echo "All True" Else Show Error. Right now i am doing this and getting error. if ; then echo "All True" else echo "Failed" fi; Error. line 8: ' Solution: Looking for (2 Replies)
Discussion started by: mkashif
2 Replies

4. Shell Programming and Scripting

Operators

I really don't know the meaning of these operators. Could someone explain the meanings so I can make my test for today? <, <=, ==, !=, >=, >, ||, &&, ! ~ , !~ Thanks! (1 Reply)
Discussion started by: Erjen
1 Replies

5. Homework & Coursework Questions

Operators

I really don't know the meaning of these operators. Could someone explain the meanings? <, <=, ==, !=, >=, >, ||, &&, ! ~ , !~ Thanks! (1 Reply)
Discussion started by: Erjen
1 Replies

6. Shell Programming and Scripting

Can you use logical operators in a case statement (bash)?

I'm pretty sure I already know the answer to this, but I want to make sure I'm not overlooking anything. I'm working on a log monitoring script and every 10 lines I want to display a summary of events. The thing is, there are a lot of possible events, that likely won't have happened, so I only want... (0 Replies)
Discussion started by: DeCoTwc
0 Replies

7. Shell Programming and Scripting

BASH - set specific user variable via string operators

Apologies for the utter triviality of this question, but we all have to start somewhere! I've also tried searching but this question is pretty vague so I didn't (a) really know what to search for or (b) get many relevant hits to what I did search for. Anyway, I'm in the process of self-teaching... (1 Reply)
Discussion started by: u5j84
1 Replies

8. Shell Programming and Scripting

operators in if loop

Hi all, I have a variable which is having the value like below, $ echo ${p} 8 15 22 30 $ My requirement is that the variable should return true when it contains only one number like below, $ echo ${p} 15 $ Otherwise, it should return false if it contains more than one number. I... (4 Replies)
Discussion started by: raghu.iv85
4 Replies

9. Shell Programming and Scripting

awk and Unary Operators in Bash

I am getting the following error /home/hagbard/chaos/resip/ictja/siculet-0.0.0/amvib/tmspan.sh: line 135: BEGIN {printf "%.0f", int((tm-(thh*60.0*60.0))/60.0)}: No such file or directory /home/hagbard/chaos/resip/ictja/siculet-0.0.0/amvib/tmspan.sh: line 138: The code is this ... (3 Replies)
Discussion started by: kristinu
3 Replies

LEARN ABOUT LINUX

bashbug

BASHBUG(1)							      bashbug								BASHBUG(1)

NAME

       bashbug - report a bug in bash

SYNOPSIS

       bashbug [--help] [--version] [bug-report-email-addresses]

DESCRIPTION

       bashbug is a utility for reporting bugs in Bash to the maintainers.

       bashbug will start up your preferred editor with a preformatted bug report template for you to fill in. Save the file and quit the editor
       once you have completed the missing fields.  bashbug will notify you of any problems with the report and ask for confirmation before
       sending it. By default the bug report is mailed to both the GNU developers and the Debian Bash maintainers. The recipients can be changed
       by giving a comma separated list of bug-report-email-addresses.

       If you invoke bashbug by accident, just quit your editor. You will always be asked for confirmation before a bug report is sent.

OPTIONS

       --help
	      Show a brief usage message and exit.

       --version
	      Show the version of bashbug and exit.

       bug-report-email-addresses
	      Comma separated list of recipients' email addresses. By default the report is mailed to both the GNU developers and the Debian Bash
	      maintainers.

ENVIRONMENT

       DEFEDITOR
	      Editor to use for editing the bug report.

       EDITOR
	      Editor to use for editing the bug report (overridden by DEFEDITOR).

SEE ALSO

       bash(1), reportbug(1), update-alternatives(8) for preferred editor.

AUTHOR

       This manual page was written by Christer Andersson <klamm@comhem.se> for the Debian project (but may be used by others).

GNU Bash 3.1							 11 December 2007							BASHBUG(1)
All times are GMT -4. The time now is 02:21 AM.
Unix & Linux Forums Content Copyright 1993-2022. All Rights Reserved.
Privacy Policy