[R] dev2bitmap error, 'gs' cannot be found

[Boel Brynedal]

Dear List,

I am using the bioconductor package Category  to do some gene enrichment
analysis, and usually save my KEGGmnplot's using a dev2bitmap command.
This has worked just fine, until suddenly earlier today I got this
error-message:

> dev2bitmap("04610_080721.jpg",type="jpeg", height = 10, width = 10,
res = 200)
Error in dev2bitmap("04610_CSF080721.jpg", type = "jpeg", height = 10,  :
  sorry, 'gs' cannot be found

I don't know what this means, it seems to be something about my
environment. 
(From dev2bitmap function:)
gsexe <- Sys.getenv("R_GSCMD")
    if (is.null(gsexe) || !nzchar(gsexe)) {
        gsexe <- "gs"
        rc <- system(paste(shQuote(gsexe), "-help > /dev/null"))
        if (rc != 0)
            stop("sorry, 'gs' cannot be found")
    }
I cant figure out how to fix this. I am not an experienced programmer.
Any help or tips would be greatly appreciated.

Thank you,
Boel

--~*~**~***~*~***~**~*~--
Boel Brynedal, MSc, PhD student
Karolinska  Institutet
Department of Clinical neuroscience