Login or Register to Ask a Question and Join Our Community


UNIX for Dummies Questions & Answers

Purpose of - (hypen) in script or command line

 
Thread Tools Search this Thread
Top Forums UNIX for Dummies Questions & Answers Purpose of - (hypen) in script or command line
# 1  
Old 07-25-2011
Bug Purpose of - (hypen) in script or command line
Hi,
I am new for unix and I am following ABS guide. What is the purpose of - (hypen ) in the below command and What it will do in this?. Can anyone explain it in detail. Rest of the things in the below command I understood somewhat.

(cd /source/directory && tar cf - . ) | (cd /dest/directory && tar xpvf -)
# 2  
Old 07-25-2011
It's common (and POSIX) convention for stdin/stdout:
Utility Conventions
"For utilities that use operands to represent files to be opened for either reading or writing, the '-' operand should be used only to mean standard input (or standard output when it is clear from context that an output file is being specified)."
 
Login or Register to Ask a Question

Previous Thread | Next Thread

10 More Discussions You Might Find Interesting

1. UNIX for Beginners Questions & Answers

General Purpose Date Script

There must be thousands of one-off solutions scattered around this forum. GNU Date is so handy because it's general but if they're asking they probably don't have it. We have some nice scripts but they tend to need dates formatted in a very particular way. This is a rough approximation which... (18 Replies)
Discussion started by: Corona688
18 Replies

2. Shell Programming and Scripting

How to replace colon in HH:MI:SS to hypen?

I have a file that contains timestamp in some of the rows in the file and the field separator is colon and some of the rows have numerical values, timestamp and characters with colon as the field separator We are looking to change colon in HH:MI:SS for the timestamp to hyphen “-“ leaving the field... (1 Reply)
Discussion started by: cumeh1624
1 Replies

3. Shell Programming and Scripting

SH script, variable built command fails, but works at command line

I am working with a sh script on a solaris 9 zone (sol 10 host) that grabs information to build the configuration command line. the variables Build64, SSLopt, CONFIGopt, and CC are populated in the script. the script includes CC=`which gcc` CONFIGopt=' --prefix=/ --exec-prefix=/usr... (8 Replies)
Discussion started by: oly_r
8 Replies

4. UNIX for Advanced & Expert Users

Sequence number merged with hypen, shell script

Hello Folks, i have to write shell scripting for given expected output manner. in given input we have to write shell script in such a way that sequence no can b merged/link between start and end digit with hyphen "-" symbol and rest of digit separated by "," Eg : For Input "2 6 7 8 11 12... (9 Replies)
Discussion started by: panchalh
9 Replies

5. Shell Programming and Scripting

Command executes on the command line but not from script

Hello guys, I have the following commands : Command 1: sudo find "../bundlepool" -name "merchandising2.html" -print0 |xargs -0 -I {} cp "rebranding/merchandising2.html" {} Command 2: find "../bundlepool" -name "merchandising2.html" -exec cp rebranding/merchandising2.html {} \; Command 3: ... (2 Replies)
Discussion started by: ihabo01
2 Replies

6. Shell Programming and Scripting

Need help! command working ok when executed in command line, but fails when run inside a script!

Hi everyone, when executing this command in unix: echo "WM7 Fatal Alerts:", $(cat query1.txt) > a.csvIt works fine, but running this command in a shell script gives an error saying that there's a syntax error. here is content of my script: tdbsrvr$ vi hc.sh "hc.sh" 22 lines, 509... (4 Replies)
Discussion started by: 4dirk1
4 Replies

7. Shell Programming and Scripting

script to fill up disk space for testing purpose

Hello everyone I am new to this forum I am working on a project and needed a test script to fill up a disk partition /tmp/data to see how the program fails. The system I am working on is a redhat 5.3. Is there anything out there? Thanks. (10 Replies)
Discussion started by: dp100022
10 Replies

8. Solaris

Purpose D option in useradd command

Hi Can any one tell about -D option in the useradd command? Thanks MaroV (3 Replies)
Discussion started by: vr_mari
3 Replies

9. Shell Programming and Scripting

Purpose of 2>&1 in the command

Can any body kindly tell me what is the purpose of 2>&1 in the following commands. nohup ./append_import.sh 1 > import1.out 2>&1 < /dev/null & nohup ./append_import.sh 2 > import2.out 2>&1 < /dev/null & (1 Reply)
Discussion started by: mmunir
1 Replies

10. UNIX for Dummies Questions & Answers

whats the purpose of the following script?

whats the purpose of the following script? who could run it? To what is the script refering that exceeds 75%? The mailbox? What does sed 's/%//' do? (1 Reply)
Discussion started by: vrn
1 Replies
Login or Register to Ask a Question