Opening file at command line

I'm using Unix at the school (alpha). To compile I usually type cxx *.cpp and it gives me an a.out file. I typed a.out and it shows me the output for the progam. If I need to type the names of the input and output files at the command line, how do I do that? When I compile by typing "cxx *.cpp" it gives me this msg:

Code:

---

ld (prelink):
processInfile.o compressed: processInfile(ifstream&, char&): multiply defined
ld:
processInfile.ocompressed: processInfile(ifstream&, char&): multiply defined

---

It creates an a.out file, but if I type a.out, it says execute permission denied. If I type "cxx *.cpp blob1.dat outfile.dat" it gives me:

Code:

---

Object file format error in: blob1.dat: read_pass1_info_malloc: bad file magic n
umber
ld:
processInfile.o compressed: processInfile(ifstream&, char&): multiply defined
Object file format error in: blob1.dat: read_cur_obj_info: bad file magic number
(0x2c32)

---