Bash File System

These functions interact with the operating system, and help improve the user experience.

opal:command_exists

Check if the specified directory exists. It’s simply a wrapper around Bash’s native file functionality. It’ll evaluate True if file exists and is a directory.

Check that a command is available on your system.

@return bool

@uses type

if opal:command_exists "eza"; then
    eza --long  "$1"
else
    ls "$1"
fi

opal:dir_exists

Check if the specified directory exists. It’s simply a wrapper around Bash’s native file functionality.

@return bool

if ! opal:dir_exists "$HOME/tmp"; then
    mkdir "$HOME/tmp"
fi

opal:ensure_dir_exists

There are times when it’s necessary to be available when writing bash scripts. This function creates it, if it’s unavailable.

Create a directory if it doesn’t exist

When you need a directory to be avaialable, this will create it if need be.

@return bool

@uses type

opal:ensure_dir_exists "$HOME/tmp"

opal:file_exists

Check if the specified file exists. It’s simply a wrapper for Bash native functionality. It’s much easier to remember this names versus a test operator.

@return bool

if ! opal:file_exists "$HOME/tmp"; then
    mkdir "$HOME/tmp"
fi

opal:symlink_exists

Check if a symlink exists

@return bool

if ! opal:symlink_exists "$HOME/symlink_name"; then
    opal:success 'The symlink "symlink_name" was found'
fi

opal:file_has_read

Check if the current user can read a file.

@param string $filepath

@return bool

if opal:file_has_read "$filepath"; then
   opal:success "File '${filepath}' has read permission"
else
   opal:failure "The file '${filepath}' cannot be read"
fi

opal:file_has_write

Check if the current user can read a file.

@param string $filepath

@return bool

if opal:file_has_write "$filepath"; then
   opal:success "File '${filepath}' has write permission"
else
   opal:failure "The file '${filepath}' cannot be written"
fi

opal:file_has_execute

Check if the current user can execute a file.

@param string $filepath

@return bool

if opal:file_has_execute "$filepath"; then
   opal:success "File '${filepath}' has execute permission"
else
   opal:failure "The file '${filepath}' cannot be executed"
fi

opal:file_has_set_uid

Determine if the file has the Set UID bit set

@param string $filepath

@return bool

if opal:file_has_set_uid "$filepath"; then
   opal:message "File '${filepath}' has Set UID permission"
fi

opal:file_has_set_gid

Determine if the file has the Set GID bit set

@param string $filepath

@return bool

if opal:file_has_set_gid "$filepath"; then
   opal:message "File '${filepath}' has Set GID permission"
fi