The UNIX Bash Scripting blog suggests: awk ‘!x[$0]++’ This command is telling awk which lines to print. The variable $0 holds the entire contents of a line and square brackets are array access. So, for each line of the file, the node of the array x is incremented and the line printed if the content … Read more
A Bash function can’t return a string directly like you want it to. You can do three things: Echo a string Return an exit status, which is a number, not a string Share a variable This is also true for some other shells. Here’s how to do each of those options: 1. Echo strings lockdir=”somedir” … Read more
Use -o, which means “or”: find Documents \( -name “*.py” -o -name “*.html” \) You’d need to build that command line programmatically, which isn’t that easy. Are you using bash (or Cygwin on Windows)? If you are, you should be able to do this: ls **/*.py **/*.html which might be easier to build programmatically.
First things first, hover the mouse over the grey area below. Not part of the answer, but absolutely has to be said: If you have a shell script that does “checkout, build, deploy” all by itself, then why are you using Jenkins? You are foregoing all the features of Jenkins that make it what it … Read more
This works in bash and zsh, tested on Linux and OS X: sed ‘s/regexp/\’$’\n/g’ In general, for $ followed by a string literal in single quotes bash performs C-style backslash substitution, e.g. $’\t’ is translated to a literal tab. Plus, sed wants your newline literal to be escaped with a backslash, hence the \ before … Read more
$? is used to find the return value of the last executed command. Try the following in the shell: ls somefile echo $? If somefile exists (regardless whether it is a file or directory), you will get the return value thrown by the ls command, which should be 0 (default “success” return value). If it … Read more
Pass variables to awk with the -v flag. x=3 A=`echo $A|awk -v y=$x ‘{print y}’` echo $A
You can use shuf: shuf -n 1 $FILE There is also a utility called rl. In Debian it’s in the randomize-lines package that does exactly what you want, though not available in all distros. On its home page it actually recommends the use of shuf instead (which didn’t exist when it was created, I believe). … Read more
yet another solution uses tr: echo $testVar | tr -d ‘\r’ cat myscript | tr -d ‘\r’ the option -d stands for delete.
The number of seconds per day are fixed with Unix timestamps. The Unix time number is zero at the Unix epoch, and increases by exactly 86400 per day since the epoch. So it cannot represent leap seconds. The OS will slow down the clock to accommodate for this. The leap seconds is simply not existent … Read more