Given struct defs of: struct gen_state { struct localuser *u; struct ast_filestream *stream; ************** int sample_queue; int playing_silence; }; struct ast_filestream { /* Everybody reserves a block of AST_RESERVED_POINTERS pointers for us */ struct ast_format *fmt; int flags; mode_t mode; char *filename; ********** char *realfilename; /* Video file stream */ struct ast_filestream *vfs; /* Transparently translate from another format -- just once */ struct ast_trans_pvt *trans; struct ast_tranlator_pvt *tr; int lastwriteformat; int lasttimeout; struct ast_channel *owner; }; and struct gen_state *state; Why does this: fprintf(child_events, "F,%10ld,%s\n", time(NULL),state->stream->filename); produce this error: app.c:166: error: dereferencing pointer to incomplete type ????? Thanks for your help.