+The given +options +(see below) +are executed and then +the Lua program in file +script +is loaded and executed. +The given +args +are available to +script +as strings in a global table named +arg. +If these arguments contain spaces or other characters special to the shell, +then they should be quoted +(but note that the quotes will be removed by the shell). +The arguments in +arg +start at 0, +which contains the string +'script'. +The index of the last argument is stored in +arg.n. +The arguments given in the command line before +script, +including the name of the interpreter, +are available in negative indices in +arg. +
+At the very start, +before even handling the command line, +lua +executes the contents of the environment variable +LUA_INIT, +if it is defined. +If the value of +LUA_INIT +is of the form +'@filename', +then +filename +is executed. +Otherwise, the string is assumed to be a Lua statement and is executed. +
+Options start with +'-' +and are described below. +You can use +'--' +to signal the end of options. +
+If no arguments are given, +then +"-v -i" +is assumed when the standard input is a terminal; +otherwise, +"-" +is assumed. +
+In interactive mode, +lua +prompts the user, +reads lines from the standard input, +and executes them as they are read. +If a line does not contain a complete statement, +then a secondary prompt is displayed and +lines are read until a complete statement is formed or +a syntax error is found. +So, one way to interrupt the reading of an incomplete statement is +to force a syntax error: +adding a +';' +in the middle of a statement is a sure way of forcing a syntax error +(except inside multiline strings and comments; these must be closed explicitly). +If a line starts with +'=', +then +lua +displays the values of all the expressions in the remainder of the +line. The expressions must be separated by commas. +The primary prompt is the value of the global variable +_PROMPT, +if this value is a string; +otherwise, the default prompt is used. +Similarly, the secondary prompt is the value of the global variable +_PROMPT2. +So, +to change the prompts, +set the corresponding variable to a string of your choice. +You can do that after calling the interpreter +or on the command line +(but in this case you have to be careful with quotes +if the prompt string contains a space; otherwise you may confuse the shell.) +The default prompts are "> " and ">> ". +
+- +load and execute the standard input as a file, +that is, +not interactively, +even when the standard input is a terminal. +
+-e stat +execute statement +stat. +You need to quote +stat +if it contains spaces, quotes, +or other characters special to the shell. +
+-i +enter interactive mode after +script +is executed. +
+-l name +call +require('name') +before executing +script. +Typically used to load libraries. +
+-v +show version information. +