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  • cppawk has some charms. :)

    From Kaz Kylheku@21:1/5 to All on Sat Mar 19 01:29:41 2022
    $ cppawk -f foo.cwk
    /dev/sda1


    $ cat foo.cwk
    #include "awkloop.h"

    function main()
    {
    awkloop ("/proc/mounts") {
    rule ($3 != "ext4") { nextrec }
    rule ($2 == "/") { print $1 }
    }
    }

    BEGIN {
    main()
    }


    $ cat awkloop.h
    #define awkloop(file) for (; getline < file || (close(file) && 0); )
    #define nextrec continue
    #define rule(cond) if (cond)


    :)

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)
  • From Ed Morton@21:1/5 to Kaz Kylheku on Mon Mar 28 07:12:18 2022
    On 3/18/2022 8:29 PM, Kaz Kylheku wrote:
    $ cppawk -f foo.cwk
    /dev/sda1


    $ cat foo.cwk
    #include "awkloop.h"

    function main()
    {
    awkloop ("/proc/mounts") {
    rule ($3 != "ext4") { nextrec }
    rule ($2 == "/") { print $1 }
    }
    }

    BEGIN {
    main()
    }


    $ cat awkloop.h
    #define awkloop(file) for (; getline < file || (close(file) && 0); )

    That would spin off into an infinite loop if getline failed since it'd
    then return a negative number which is non-zero and therefore considered
    "true" in a conditional context. `getline < file` needs to be `(getline
    < file) > 0`. See http://awk.freeshell.org/AllAboutGetline.

    Ed.

    #define nextrec continue
    #define rule(cond) if (cond)


    :)

    --- SoupGate-Win32 v1.05
    * Origin: fsxNet Usenet Gateway (21:1/5)