我正在编写一个 pty 本机扩展并希望链接 libutil 以便我可以使用 forkpty 和 openpty from <pty.h>.
我正在使用从官方指南中获取的两个命令：
g++ -fPIC -lutil -I/home/crunchex/work/dart-sdk -c pty.cc -o pty.o
gcc -shared -Wl,-soname,libpty.so -o libpty.so pty.o
我收到以下错误：
/home/crunchex/work/dart-sdk/bin/dart: symbol lookup error: /home/crunchex/work/pty/bin/packages/pty/libpty.so: undefined symbol: forkpty
这可能更像是一个 g++/gcc 问题，但据我所知，我通过添加 -lutil 并包括<pty.h>. libutil.so 安装在我的 Ubuntu 14.04 系统上，所以我很确定它就在那里。
这是我的测试扩展：
#include <string.h>
#include <pty.h>
#include "include/dart_api.h"
Dart_NativeFunction ResolveName(Dart_Handle name,
int argc,
bool* auto_setup_scope);
DART_EXPORT Dart_Handle pty_Init(Dart_Handle parent_library) {
if (Dart_IsError(parent_library)) {
return parent_library;
}
Dart_Handle result_code =
Dart_SetNativeResolver(parent_library, ResolveName, NULL);
if (Dart_IsError(result_code)) {
return result_code;
}
return Dart_Null();
}
Dart_Handle HandleError(Dart_Handle handle) {
if (Dart_IsError(handle)) {
Dart_PropagateError(handle);
}
return handle;
}
//\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\//
//\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\//
void PtyFork(Dart_NativeArguments args) {
Dart_EnterScope();
struct winsize winp;
winp.ws_col = 80;
winp.ws_row = 24;
winp.ws_xpixel = 0;
winp.ws_ypixel = 0;
int master = -1;
char name[40];
pid_t pid = forkpty(&master, name, NULL, &winp);
Dart_ExitScope();
}
//\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\//
//\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\/\//
struct FunctionLookup {
const char* name;
Dart_NativeFunction function;
};
FunctionLookup function_list[] = {
{"PtyFork", PtyFork},
{NULL, NULL}};
Dart_NativeFunction ResolveName(Dart_Handle name, int argc, bool* auto_setup_scope) {
if (!Dart_IsString(name)) return NULL;
Dart_NativeFunction result = NULL;
Dart_EnterScope();
const char* cname;
HandleError(Dart_StringToCString(name, &cname));
for (int i=0; function_list[i].name != NULL; ++i) {
if (strcmp(function_list[i].name, cname) == 0) {
result = function_list[i].function;
break;
}
}
Dart_ExitScope();
return result;
}