22 мар. 2022 г. · You can use command -v to check for availability of a command. No need to check its output, command will tell you via its exit status if it succeeded to find ...

13 нояб. 2017 г. · You probably want to use the command command, eg: command -v <the_command> For more discussion see the following StackOverflow posts.

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.

29 янв. 2019 г. · At the start of your script, check if figlet exists, and if it does not, define a shell function that does nothing: type figlet >/dev/null 2 ...

9 июл. 2012 г. · There are two commands command -v type that can be used to check if the command exists. But it also returns a true for user written scripts.

25 июн. 2015 г. · if [ -v $somevar ] then echo "Variable somevar exists!" else echo "Variable somevar does not exist!" And the closest question to that was this, ...

28 янв. 2023 г. · Typeset -f myfunction returns true and produces no output when the function is defined, and otherwise returns false and outputs an error message.

1 сент. 2011 г. · In Bash the type shell built-in gives information about the executable things: aliases, functions, executables. See help type for details.

15 мар. 2024 г. · The trick was to force tcsh to enable command hashing, which as it turns out get's disabled if it's called with "-f" flag, which was the ...

9 окт. 2018 г. · You can simply do this : #to check if it's a regular file [ -f "/you/file.file" ] && echo 1 || echo 0 #to check if a file exist [ -e "/you/file.file"