#!/bin/sh if [ “$#” -ne 1 ] || ! [ -d “$1” ]; then echo “Usage: $0 DIRECTORY” >&2 exit 1 fi Translation: If number of arguments is not (numerically) equal to 1 or the first argument is not a directory, output usage to stderr and exit with a failure status code. More friendly error … Read more
The problems with the existing answers: inability to handle filenames with embedded spaces or newlines. in the case of solutions that invoke rm directly on an unquoted command substitution (rm `…`), there’s an added risk of unintended globbing. inability to distinguish between files and directories (i.e., if directories happened to be among the 5 most … Read more
eval takes a string as its argument, and evaluates it as if you’d typed that string on a command line. (If you pass several arguments, they are first joined with spaces between them.) ${$n} is a syntax error in bash. Inside the braces, you can only have a variable name, with some possible prefix and … Read more
To exit a script you can use, import sys sys.exit() You can also provide an exit status value, usually an integer. import sys sys.exit(0) Exits with zero, which is generally interpreted as success. Non-zero codes are usually treated as errors. The default is to exit with zero. import sys sys.exit(“aa! errors!”) Prints “aa! errors!” and … Read more
The variable $$ contains the PID.
The following will print the line matching TERMINATE till the end of the file: sed -n -e ‘/TERMINATE/,$p’ Explained: -n disables default behavior of sed of printing each line after executing its script on it, -e indicated a script to sed, /TERMINATE/,$ is an address (line) range selection meaning the first line matching the TERMINATE … Read more
You can either run it like this (but this shows a window for a while): PowerShell.exe -WindowStyle hidden { your script.. } Or you use a helper file I created to avoid the window called PsRun.exe that does exactly that. You can download the source and exe file from Run scheduled tasks with WinForm GUI … Read more
To wait for any process to finish Linux (doesn’t work on Alpine, where ash doesn’t support tail –pid): tail –pid=$pid -f /dev/null Darwin (requires that $pid has open files): lsof -p $pid +r 1 &>/dev/null With timeout (seconds) Linux: timeout $timeout tail –pid=$pid -f /dev/null Darwin (requires that $pid has open files): lsof -p $pid … Read more
Generally, it would be better to pass info to the script via a parameter rather than a global (environment) variable. But if that is what you need to do you can do it this way: $env:FOO = ‘BAR’; ./myscript The environment variable $env:FOO can be deleted later like so: Remove-Item Env:\FOO
awk ‘{sum+=$3}; END {printf “%f”,sum/NR}’ ${file}_${f}_v1.xls >> to-plot-p.xls print will insert a newline by default. You dont want that to happen, hence use printf instead.