Runtime Errors when reversing a list in Prolog -

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following learning exercises/tutorials online encounter bellow error when running simple prolog program. 

testreverse :-   transimage(reserselist,'imagein.pgm','imageout.pgm').  transimage(r,in,out) :-    read_pgm(in,pgm),    transf_pgm(r,pgm,pgm2),    write_pgm(out,pgm2).  transf_pgm(r, pgm(a,b,h,w,m,l),  pgm(a,b,h,w,m,l2)) :-    term =.. [r,l,l2],    call(term).  reserselist([],[]). reserselist([x|r],reversed):-     reserselist(r, revlist),     append(revlist,[x],reversed).

and runtime error getting in swi-prolog is

10 ?- testreverse |    . error: read_pgm/2: undefined procedure: fread/4 error:   however, there definitions for: error:         read/1 error:         read/2

any ideas why? new prolog, literally 2 days online tutorials, accept apologies in advance if make further questions regarding answer. thank you.

according error message havent defined fread/4.
on other hand, in code gave read_pgm/2 not defined either (unless i'm missing something).

possible reasons:
definition in other file.
fread/4 not implemented in prolog implementation.
didnt load library fread/4.

i think should post rest of code , prolog implementation use.
if use swi-prolog, dont think there fread/4.


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