objective c - How to redirect STDOUT to a NSTextView? -

could show me how redirect stdout nstextview?

and whether info print nslog belong std?

thanks

the code below uses dup2 plug stdout onto write-end of nspipe object. read-end observed gcd dispatch source, reads data pipe , appends textview.

nspipe* pipe = [nspipe pipe]; nsfilehandle* pipereadhandle = [pipe filehandleforreading]; dup2([[pipe filehandleforwriting] filedescriptor], fileno(stdout)); source = dispatch_source_create(dispatch_source_type_read, [pipereadhandle filedescriptor], 0, dispatch_get_global_queue(dispatch_queue_priority_default, 0)); dispatch_source_set_event_handler(source, ^{     void* data = malloc(4096);     ssize_t readresult = 0;         {         errno = 0;         readresult = read([pipereadhandle filedescriptor], data, 4096);     } while (readresult == -1 && errno == eintr);     if (readresult > 0)     {         //appkit ui should updated main thread         dispatch_async(dispatch_get_main_queue(),^{             nsstring* stdoutstring = [[nsstring alloc] initwithbytesnocopy:data length:readresult encoding:nsutf8stringencoding freewhendone:yes];             nsattributedstring* stdoutattributedstring = [[nsattributedstring alloc] initwithstring:stdoutstring];             [self.logview.textstorage appendattributedstring:stdoutattributedstring];         });     }     else{free(data);} }); dispatch_resume(source); 

nslog(@"...") not output stdout though - prints stderr. if want redirect textview, change

dup2([[pipe filehandleforwriting] filedescriptor], fileno(stdout)); 

to

dup2([[pipe filehandleforwriting] filedescriptor], fileno(stderr));