I use the following ghostscript commands
pdf2ps input.pdf - | psnup -pA4 -4 >> output.ps ps2pdf output.ps output.pdf rm output.ps
to merge multiple pages (in this case 4) from input file to one sheet in outupt file.
How can I modify pipelining so that I won't have to use 2 commands, but just a single one liner? Is there any other commandline tool that would do the same and can work directly on pdf files?