This repository groups all dev findings, snippets and tests related to the development of the bash commons.
- Bash string extraction pattern details (pattern
${<string variable name>:<offset>:<length>}) - Problems with bash's associative arrays
- Variable scope clarifications
- bash aliases are not adapted to create wrapper functions in libraries like the bash commons because in non-interactive mode their interpretation is usually disabled - aliases defined in the library might simply be ignored. It's safer to create "real" functions, as it was done with bash common's move_file() f.ex.
Get piped input:
[ -p /dev/stdin ] && echo "$(cat)"Check if a command is defined:
[ -n "$(type -t "$command_name")" ]It works for binaries, shell built-ins, (sourced) functions, etc.
The snippet checks for bash functions:
[ "$(type -t "$function_name")" = "function" ]These 3 snippets are provided as functions in snippet_functions.sh, with documentation.
Simplified script directory resolution (f.ex. in an installer before bash_commons are available):
# Exit with error message on file symlinks, set $script_folder to the directory in which the script is located (folder symlinks resolved)
symlink_error_msg="Error: Please don't call ... through file symlinks, this confuses the script about its own location. Call it directly. Aborting..."
if [ -h "${BASH_SOURCE[0]}" ]; then echo "$symlink_error_msg"; exit 1; fi
script_folder="$(cd -P "$(dirname "${BASH_SOURCE[0]}")" >/dev/null && pwd)"Important: this code has to run before files are sourced, subshells are launched etc. because such operations affect $BASH_SOURCE