[ns] problem running nam, startx, startxwin.bat

whenever i try to run nam, startx, startxwin.bat i get a message the procedure entry point _impure_ptr could not be located in dynamic link library cygwin1.dll can someone help me for what causes this error and kindly tell me its solution. thanks in advance

[ns] trouble in executing wireless examples

sir i have tried to execute wireless1.tcl file and have got following error *$ ns wireless1.tcl$ * num_nodes is set 3 warning: Please use -channel as shown in tcl/ex/wireless-mitf.tcl INITIALIZE THE LIST xListHead Loading connection pattern... couldn't read file ../mobility/scene/cbr-3-test: no