gistfile1.c

#include <stdio.h>
#include <julia/julia.h>
#include <pthread.h>

JULIA_DEFINE_FAST_TLS

extern "C" double __stdcall c_func(int i);

extern "C" double __stdcall c_func(int i)
{
    printf("[C %08x] i = %d\n", pthread_self(), i);
    printf("c\n");
    // Call the Julia sqrt() function to compute the square root of i, and return it
    jl_function_t *sqrt = jl_get_function(jl_base_module, "sqrt");
    jl_value_t *arg = jl_box_int32(i);
    double ret = jl_unbox_float64(jl_call1(sqrt, arg));
    printf("ccc\n");
    return ret;
}

int main()
{
    jl_init();

    printf("c_func = %f\n", c_func(2));
    // Define a Julia function func() that calls our c_func() defined in C above
    jl_eval_string("func(i) = @ccall c_func(i::Int32)::Float64");
    if (jl_exception_occurred())
        printf("%s \n", jl_typeof_str(jl_exception_occurred()));
    printf("a\n");

    // Call func() multiple times, using multiple threads to do so
    jl_eval_string("println(Threads.threadpoolsize())");
    if (jl_exception_occurred())
        printf("%s \n", jl_typeof_str(jl_exception_occurred()));

    printf("aa\n");
    jl_eval_string("use(i) = println(\"[J $(Threads.threadid())] i = $(i) -> $(func(i))\")");
    if (jl_exception_occurred())
        printf("%s \n", jl_typeof_str(jl_exception_occurred()));
    printf("aaa\n");
    jl_eval_string("val=2");
    if (jl_exception_occurred())
        printf("%s \n", jl_typeof_str(jl_exception_occurred()));
    printf("aaabb\n");
    jl_eval_string("println(val)");
    if (jl_exception_occurred())
        printf("%s \n", jl_typeof_str(jl_exception_occurred()));

    jl_eval_string("ccall(:c_func,stdcall, Float32, (Int32,), val)");
    if (jl_exception_occurred())
        printf("%s \n", jl_typeof_str(jl_exception_occurred()));

    printf("aaa use\n");
    jl_eval_string("Threads.@threads for i in 1:5 use(i) end");
    if (jl_exception_occurred())
        printf("%s \n", jl_typeof_str(jl_exception_occurred()));
    printf("aab\n");
    jl_atexit_hook(0);
}

gistfile2.md

macos

build

cc main.c -I ~/.julia/juliaup/julia-1.10.0+0.x64.apple.darwin14/include -I ~/.julia/juliaup/julia-1.10.0+0.x64.apple.darwin14/include/julia -L ~/.julia/juliaup/julia-1.10.0+0.x64.apple.darwin14/lib -ljulia

RUN

JULIA_NUM_THREADS=8 DYLD_LIBRARY_PATH=~/.julia/juliaup/julia-1.10.0+0.x64.apple.darwin14/lib  ./a.out