Intercept exit then call gmt module

test/Makefile

@@ -0,0 +1,32 @@
+SHELL=/bin/bash
+OPTFLAGS=-O2 -flto -g
+EXPORTFLAGS=-fvisibility=hidden -fpic -Wl,--export-dynamic
+CPPFLAGS=-std=gnu++11 -I../include -I/home/michael/tmp/gmt5/include/gmt
+LIBSFLAGS=-L/home/michael/tmp/gmt5/lib64 -Wl,-rpath /home/michael/tmp/gmt5/lib64 -lgmt -ldl -lpthread $(MODLIBS)
+WARNFLAGS=-Wall
+
+CFLAGS=$(OPTFLAGS) $(EXPORTFLAGS) $(WARNFLAGS) $(CPPFLAGS)
+LDFLAGS=$(OPTFLAGS) $(EXPORTFLAGS) $(WARNFLAGS) $(LIBSFLAGS)
+
+CC=g++
+
+SOURCE = $(wildcard *.cpp)
+DEPENDS = $(subst .cpp,.d,$(SOURCE))
+OBJECTS = $(subst .cpp,.o,$(SOURCE)) 
+
+gmttest: $(OBJECTS) $(MODOBJECTS)
+	 $(CC) -o $@ $(OBJECTS) $(MODOBJECTS) $(LDFLAGS)
+
+include $(DEPENDS)
+
+%.o: %.cpp
+	 $(CC) -c $(CFLAGS) -o $@ $<
+
+%.d: %.cpp
+	 $(CC) $(CPPFLAGS) -MM -MT $(subst .cpp,.o,$<) $< | sed 's%\(^.*\):%\1 $@ :%g' >$@
+
+clean:
+	 rm -f *.o *.d
+
+distclean: clean
+	 rm -f gmttest

test/gmttest.cpp

@@ -0,0 +1,99 @@
+#include <gmt.h>
+#include <iostream>
+#include <string>
+#include <unistd.h>
+#include <sys/wait.h>
+
+int print_func(FILE* fd, const char* str)
+{
+ std::cout<<"PRINT: "<<str<<std::endl;
+ return 0;
+}
+
+struct gmtworkthreadpars
+{
+ void* api;
+ const char* module;
+ struct GMT_OPTION* opts;
+ int fd;
+ int ret;
+};
+
+void gmtonexithandler(int ret, void* x)
+{
+ reinterpret_cast<struct gmtworkthreadpars*>(x)->ret=ret;
+ close(reinterpret_cast<struct gmtworkthreadpars*>(x)->fd);
+ pthread_exit(&(reinterpret_cast<struct gmtworkthreadpars*>(x)->ret));
+}
+
+void* gmtworkthread(void* x)
+{
+ struct gmtworkthreadpars* p=reinterpret_cast<struct gmtworkthreadpars*>(x);
+ on_exit(gmtonexithandler,x);
+ GMT_Append_Option(p->api,GMT_Make_Option(p->api,'>',const_cast<char*>(("/dev/fd/"+std::to_string(p->fd)).c_str())),p->opts);
+ p->ret=GMT_Call_Module(p->api,p->module,GMT_MODULE_OPT,p->opts);
+ exit(p->ret);
+ return 0;
+}
+
+int callgmtmodule(void *api, const char *module, struct GMT_OPTION *opts, std::string& res)
+{
+ int pipefd[2];
+ ssize_t br;
+ char buffer[4096];
+ pthread_t wthr;
+ struct gmtworkthreadpars p;
+ int *pret;
+
+ pipe(pipefd);
+ p.api=api;
+ p.module=module;
+ p.opts=opts;
+ p.fd=pipefd[1];
+
+ pthread_create(&wthr,0,&gmtworkthread,&p);
+
+ res.erase();
+ //read(pipefd[0],buffer,1);
+ //close(pipefd[1]);
+ do
+ {
+  br=read(pipefd[0],buffer,4096);
+  std::cout<<res.length()<<" "<<br<<std::endl;
+  res.append(buffer,br);
+ } while(0!=br);
+ close(pipefd[0]);
+ res.shrink_to_fit();
+ pthread_join(wthr,reinterpret_cast<void**>(&pret));
+
+ return *pret;
+}
+
+
+int main()
+{
+ char* text="GMT";
+ //void* out;
+ void* gmtapi;
+ std::string args="-R130/160/40/60 -JM12c -Xa2c -Ya2c -B5/5/swNE --GMT_HISTORY=f --FONT_ANNOT_PRIMARY=14p,Times-Bold,red";
+ struct GMT_OPTION* opts;
+ int io,ret;
+ char fname[16];
+ std::string out;
+
+ gmtapi=GMT_Create_Session(text,2,3,print_func);
+ io=GMT_Register_IO(gmtapi,GMT_IS_TEXTSET,GMT_IS_DUPLICATE,GMT_IS_NONE,GMT_OUT,0,0);
+ GMT_Encode_ID(gmtapi,fname,io);
+ opts=GMT_Create_Options(gmtapi,0,(void*)args.c_str());
+ //ret=GMT_Init_IO(gmtapi,GMT_IS_TEXTSET,GMT_IS_NONE,GMT_OUT,5,0,opts);
+ std::cout<<io<<" "<<GMT_NOTSET<<" "<<fname<<" "<<ret<<std::endl;
+
+ ret=callgmtmodule(gmtapi,"psbasemap",opts,out);
+ std::cout<<"Return value: "<<ret<<std::endl;
+ std::cout<<out.max_size()<<" "<<out.capacity()<<" "<<out.size()<<std::endl;
+
+ GMT_Destroy_Options(gmtapi,&opts);
+ GMT_Destroy_Session(gmtapi);
+
+ return 0;
+}