鱼壳循环计数器

Question

I'm trying to count pages of PDF documents in a directory - which works fine except I cannot get the counter variable to increase. In the directory are two documents with 1 Page and 4 Pages. The return of my below script is:

1 
4

why isn't it incrementing $i ?

#!/usr/local/bin/fish


set i 0

for pdf in *.pdf
     set i (math i + (pdfinfo $pdf | grep Pages | awk '{print $2}'))    
     echo $i
end

Answer 1

Another approach: do the math inside awk:

for p in **.pdf; pdfinfo $p; end | awk '$1 == "Pages:" {sum += $2} END {print sum}'

To capture that:

set npages (
    for p in **.pdf
        pdfinfo $p 
    end | awk '$1 == "Pages:" {sum += $2} END {print sum}'
)
echo $npages

Answer 2

Found the issue at hand - whitespace made it problematic...

By doing **.pdf it gets recursive through all folders...

#!/usr/local/bin/fish


set i 0

for pdf in **.pdf
     set i (math $i+(pdfinfo $pdf | grep Pages | awk '{print $2}')) 
     echo $i
 end