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redirect COPY of stdout to log file from within bash script itself
...ptured - i.e. your
# log file would not contain any error messages.
# SEE (and upvote) the answer by Adam Spiers, which keeps STDERR
# as a separate stream - I did not want to steal from him by simply
# adding his answer to mine.
exec 2>&1
echo "foo"
echo "bar" >&2
Note that this is...
Java switch statement: Constant expression required, but it IS constant
...
I understand that the compiler needs the expression to be known at compile time to compile a switch, but why isn't Foo.BA_ constant?
While they are constant from the perspective of any code that executes after the fields have been i...
Git pull a certain branch from GitHub
...have a project with multiple branches. I've been pushing them to GitHub , and now that someone else is working on the project I need to pull their branches from GitHub. It works fine in master. But say that someone created a branch xyz . How can I pull branch xyz from GitHub and merge it into br...
Express.js - app.listen vs server.listen
... get it. What is the difference between creating an app using Express.js and starting the app listening on port 1234, for example:
...
'AND' vs '&&' as operator
I have a codebase where developers decided to use AND and OR instead of && and || .
10 Answers
...
NSUserDefaults - How to tell if a key exists
I'm working on a small iPhone app, and I am using NSUserDefaults as my data persistence. It only has to keep track of a few things, such as some names and some numbers so I figure I might as well keep it simple.
...
Is it faster to count down than it is to count up?
... to count down than to count up.
For example if you need to use a FOR loop and the loop index is not used somewhere (like printing a line of N * to the screen)
I mean that code like this:
...
How to prune local tracking branches that do not exist on remote anymore
...es.
This line should do the trick (requires bash or zsh, won't work with standard Bourne shell):
git branch -r | awk '{print $1}' | egrep -v -f /dev/fd/0 <(git branch -vv | grep origin) | awk '{print $1}' | xargs git branch -d
This string gets the list of remote branches and passes it into egrep...
MySQL “WITH” clause
...RDBMS products that support common table expressions:
Oracle 9i release 2 and later:
http://www.oracle-base.com/articles/misc/with-clause.php
Microsoft SQL Server 2005 and later:
http://msdn.microsoft.com/en-us/library/ms190766(v=sql.90).aspx
IBM DB2 UDB 8 and later:
http://publib.boulder.ibm.com/i...
How to convert a string to lower case in Bash?
...
The are various ways:
POSIX standard
tr
$ echo "$a" | tr '[:upper:]' '[:lower:]'
hi all
AWK
$ echo "$a" | awk '{print tolower($0)}'
hi all
Non-POSIX
You may run into portability issues with the following examples:
Bash 4.0
$ echo "${a,,}"
hi all...