I want to execute imp_serial but there is an error, plz help me

Dear Lammps users
I wanted to execute imp_serial for first time but there was an error,plz help me

WARNING on proc 0: Cannot open log.lammps for writing (…/lammps.cpp:318)

> LAMMPS (11 Jul 2014-ICMS)
> WARNING: OMP_NUM_THREADS environment is not set. (../comm.cpp:85)
>   using 1 OpenMP thread(s) per MPI task
Thank you

This means you probably do not have write permission in that directory, or you have no disk space left.

Use chmod to change permission or use some other directories.