Please support our Shell Scripting advertiser: Programming Forums
Views: 2337 | Replies: 6
 |
•
•
Join Date: Jun 2005
Posts: 2
Reputation: 
Rep Power: 0
Solved Threads: 0
Newbie Poster
Test with "[[ ... ]]" executing both, the && and the || clause Hi,
Maybe I should just make a break and go through this again by myself, but there is no more coffee, so there is no break for me
I want to check for a given dir, exit with a message if it exists, or create the given dir otherwise.
What happens is, that the shell executes the && Branch and wont exit afterwards but executes the || branch, too. Obviously mkdir throws an ugly error when the directory exists.
Dont get me wrong, I know how to make it work with the usual if construct, but I cant sleep well tonight, when I dont use a one-liner
^^ do YOU see where I made a mistake?
hugs,
schbrongx
Maybe I should just make a break and go through this again by myself, but there is no more coffee, so there is no break for me
I want to check for a given dir, exit with a message if it exists, or create the given dir otherwise.
What happens is, that the shell executes the && Branch and wont exit afterwards but executes the || branch, too. Obviously mkdir throws an ugly error when the directory exists.
Dont get me wrong, I know how to make it work with the usual if construct, but I cant sleep well tonight, when I dont use a one-liner
[[ -d ${DIR_CUSTOMER} ]] && (echo "*** Information: Directory ${DIR_CUSTOMER} already exists!"; exit 1;) || (echo "*** Creating ${DIR_CUSTOMER}"; mkdir ${DIR_CUSTOMER};)^^ do YOU see where I made a mistake?
hugs,
schbrongx
•
•
Join Date: May 2005
Posts: 215
Reputation:
Rep Power: 4
Solved Threads: 0
Posting Whiz in Training
what do the double brackets accomplish in the code above
[[ -d ${DIR_CUSTOMER} ]] •
•
Join Date: Jun 2005
Posts: 2
Reputation:
Rep Power: 0
Solved Threads: 0
Newbie Poster
the brackets initiate a test.
[[ -d DIRECTORY ]] tests for the existence of a directory
[[ -e FILE ]] tests if a file exists
etc. etc.
[[ $VAR -gt 5 ]] tests, if $VAR' s content is greater then 5, etc. etc.
[[ -d DIRECTORY ]] tests for the existence of a directory
[[ -e FILE ]] tests if a file exists
etc. etc.
[[ $VAR -gt 5 ]] tests, if $VAR' s content is greater then 5, etc. etc.
•
•
Join Date: May 2005
Posts: 215
Reputation:
Rep Power: 4
Solved Threads: 0
Posting Whiz in Training
can't that be accomplished with a single set of brackets, are the double set nessesary?
•
•
Join Date: Nov 2004
Posts: 21
Reputation:
Rep Power: 5
Solved Threads: 0
Newbie Poster
•
•
•
•
Originally Posted by shanenin
can't that be accomplished with a single set of brackets, are the double set nessesary?
Look at this: [[ vs ]
vlad
+-----------------------------------+
| #include <disclaimer.h> |
+-----------------------------------+
+-----------------------------------+
| #include <disclaimer.h> |
+-----------------------------------+
•
•
Join Date: May 2005
Posts: 215
Reputation:
Rep Power: 4
Solved Threads: 0
Posting Whiz in Training
Thanks fot the nice link, that clears it up :-)
•
•
Join Date: Jun 2005
Posts: 1
Reputation:
Rep Power: 0
Solved Threads: 0
Newbie Poster
hey there I'm just registered today, if it's not late I do have the soultion for ur Q
[[ -d ${DIR_CUSTOMER} ]]
&& (echo "*** Information: Directory ${DIR_CUSTOMER} already exists!"; exit 0
|| (echo "*** Creating ${DIR_CUSTOMER}"; mkdir ${DIR_CUSTOMER}
[[ -d ${DIR_CUSTOMER} ]]
&& (echo "*** Information: Directory ${DIR_CUSTOMER} already exists!"; exit 0
|| (echo "*** Creating ${DIR_CUSTOMER}"; mkdir ${DIR_CUSTOMER}
|
•
•
•
•
Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Linear Mode
