C11 also adds support for variadic templates, which can be used to provide a way to push a function of any arity into Lua without needing to write the marshalling code yourself or running a preprocessor: // Standard C API is, of course, supported int createfoo(luaState. const); lua::push(state, createfoo); // Fundamental types work, too. When a C function is created, it is possible to associate some values with it, thus creating a C closure; these values are called upvalues and are accessible to the function whenever it is called (see c:func:luapushcclosure). Whenever a C function is called, its.

In Lua 5.3 table related functions in the C API receive and return lua_Integer.

But, lua_createtable still receives int.

In the example function below the length of the source table is used to create a copy which is the same size.

But, a cast is required to silence the warning:

warning: conversion to ‘int’ from ‘lua_Integer’ may alter its value [-Wconversion]

Searching on the Lua mailing list I found the following thread which is about Lua 5.2 (applies to earlier versions too I'm assuming):

Quote: Roberto Ierusalimschy (7 Aug 2012)

The size of tables is already limited to 2147483647 elements. Lua internally uses 'int' to index all its arrays (except for strings/byte arrays). It is a pain to work with unsigned values (such as size_t) everywhere; ptrdiff_t has no garanties at all.

Is this still the case for Lua 5.3 which uses long long for lua_Integer? Is the cast to int from lua_Integer as used in the example above safe in Lua 5.3?

Lua C Api Create Table Command

The size of a table (number of elements) is still limited to 'int'. That does not prevent a table from having arbitrary lua_Integer keys (as long as the table is not a proper sequence).

Is there Predefined-Macros define about byte order in armcc

c,armcc,predefined-macro

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c,format,sscanf,c-strings

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c,go,xlib,cgo

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c,exec,ipc

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Disadvantages of calling realloc in a loop

c,memory-management,out-of-memory,realloc

When you allocate/deallocate memory many times, it may create fragmentation in the memory and you may not get big contiguous chunk of the memory. When you do a realloc, some extra memory may be needed for a short period of time to move the data. If your algorithm does...

free causing different results from malloc

c,string,malloc,free

Every time you are creating your string, you are not appending a null terminator, which causes the error. So change this: for(j=0; j<rem_len; j++) { if(j != i) { remaining_for_next[index_4_next] = remaining[j]; index_4_next++; } } to this: for(j=0; j<rem_len; j++) { if(j != i) { remaining_for_next[index_4_next] = remaining[j]; index_4_next++; }...

Text justification C language

c,text,alignment

From printf's manual: The field width An optional decimal digit string (with nonzero first digit) specifying a minimum field width. If the converted value has fewer characters than the field width, it will be padded with spaces on the left (or right, if the left-adjustment flag has been given). Instead...

Is i=i+1 an undefined behaviour?

c,increment,undefined-behavior

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C programming - Confusion regarding curly braces

c,scope

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Segmentation fault with generating an RSA and saving in ASN.1/DER?

c,openssl,cryptography,rsa

pub_l = malloc(sizeof(pub_l)); is simply not needed. Nor is priv_l = malloc(sizeof(priv_l));. Remove them both from your function. You should be populating your out-parameters; instead you're throwing out the caller's provided addresses to populate and (a) populating your own, then (b) leaking the memory you just allocated. The result is...

What does `strcpy(x+1, SEQX)` do?

c,strcpy

The pointer + offset notation is used as a convenient means to reference memory locations. In your case, the pointer is provided by malloc() after allocating sufficient heap memory, and represents an array of M + 2 elements of type char, thus the notation as used in your code represents...

Recursive signal call using kill function

c,signals

Historically, lots of details about how signals work have changed. For instance, in the earliest variant, the processing of the signal reverted to default when the handler was called, and the handler had to re-establish itself. In this situation, sending the signal from the handler would kill the process. Currently,...

How to increment the value of an unsigned char * (C)

c++,c,openssl,byte,sha1

I am assuming your pointer refers to 20 bytes, for the 160 bit value. (An alternative may be text characters representing hex values for the same 160 bit meaning, but occupying more characters) You can declare a class for the data, and implement a method to increment the low order...

getchar() not working in c

c,while-loop,char,scanf,getchar

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loops,for-loop,lua,order

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Run Lua script from Python

python,lua,lupa

You can use a subprocess to run your Lua script and provide the function with it's arguments. import subprocess result = subprocess.check_output(['lua', '-l', 'demo', '-e', 'test('a', 'b')']) print(result) result = subprocess.check_output(['lua', '-l', 'demo', '-e', 'test2('a')']) print(result) the -l requires the given library (your script) the -e is the code that...

C binary tree sort - extending it

c,binary-tree,binary-search-tree

a sample to modify like as void inorder ( struct btreenode *, int ** ) ; int* sort(int *arra