動態調用的DEMO

#####
A.C
[
#include <stdio.h>

int a(char *s)
{
    fprint(stdout,"a called : %s/n",s);
    retuin 0;
}

]
#####
B.C
[
#include <stdio.h>

int b(char *s)
{
    fprint(stdout,"b called : %s/n",s);
    retuin 0;
}

]
#####
dll.c
[[[

include <stdio.h>
include <string.h>
include <stdlib.h>
include <unistd.h>
include <dlfcn.h>

int main(int argc, char **argv)
{
    char fun_name[32];
    char so_name[]= "./tmp/libz.so";
    void *hd;
    int (*app)(char *);
    int rc = 0;
    
    hd = dlopen(so_name, RTLD_LAZY);
    if (dlerror() != null) {
        fprintf(stderr, "dlopen error/n");
        return -1;
    }
 
    strcpy(fun_name,"a");
    app = dlsym(hd, fun_name);
    if (dlerror() != null) {
        fprintf(stderr, "dlsym error/n");
        dlclose(hd);
        return -2;
    }
 
    rc = app("aaa");
    if (rc < 0) {
        fprintf(stderr, "Call error [%d]/n", rc);
    }
    else {
        fprintf(stderr, "Call OK [%d]/n", rc);
    }

    strcpy(fun_name,"b");
    app = dlsym(hd, fun_name);
    if (dlerror() != null) {
        fprintf(stderr, "dlsym error/n");
        dlclose(hd);
        return -3;
    }
 
    rc = app("bbb");
    if (rc < 0) {
        fprintf(stderr, "Call error [%d]/n", rc);
    }
    else {
        fprintf(stderr, "Call OK [%d]/n", rc);
    }
   
   
    dlclose(hd);
    return 0;
}
]]]]
#####