3 дек. 2015 г. · I want to combine multiple conditions in a shell if statement, and negate the combination. I have the following working code for a simple combination of ...

30 июн. 2016 г. · I want to check the condition like below. Line should not starts with # symbol: if[ ! ["$Line" == "#*"] ]; then But this is not working.

16 янв. 2014 г. · I have a shell script where we have following lines if [ -z "$xyz" ] and if [ -n "$abc" ] , but I am not sure what their purpose is. Can ...

5 окт. 2016 г. · The ! keyword is POSIX but not Bourne while ! has been supported by the [ / test command from the start. So [ ! ... ] is more portable than ! [ ... ] .

9 мар. 2019 г. · I wrote a small bash script. It will try to find the word ERROR. If found the resulting value will be non-zero numeric (for example 25. I ...

27 авг. 2016 г. · I am a little bit confused on what do these operators do differently when used in bash (brackets, double brackets, parenthesis and double parenthesis).

16 окт. 2011 г. · If you want to test whether a command succeeded or not, use the command itself directly with if, as shown above.

30 нояб. 2015 г. · I have a script that fails to detect zero length strings,the script uses [ -n $value ] in a bash conditional expression.

8 сент. 2012 г. · Yes you can, but using -o for "or" is marked as obsolete in the POSIX standard, as is using -a for "and". New code should not use -o or -a .

1 окт. 2014 г. · Comes down to a readability issue depending on what you are doing (in my case, checking if files or directories exist, and if not, making them, ...