Fix spawn_spec.rb for Travis arm64 environment.
The process group id (/proc/[pid]/stat 5th field) is 0 in the Travis arm64 environment.
This is a case where it is available.
$ cat /proc/4543/stat 4543 (ruby) S 4525 4525 1384 34818 4525 4194304 37443 1754841 0 0 366 105 2291 391 20 0 3 0 1381328 1428127744 11475 18446744073709551615 94195983785984 94195986670225 140728933833312 0 0 0 0 0 1107394127 0 0 0 17 2 0 0 1 0 0 94195987686512 94195987708942 94196017770496 140728933835483 140728933835595 140728933835595 140728933842904 0
This is a case where it is not available in Travis arm64 environment.
$ cat /proc/19179/stat 19179 (ruby) S 19160 0 0 0 -1 4194560 37618 1710547 313 163 770 665 5206 1439 20 0 2 0 17529566 1196347392 10319 18446744073709551615 187650811428864 187650815023116 281474602721280 0 0 0 0 4096 1107390031 0 0 0 17 22 0 0 0 0 0 187650815091456 187650815114064 187651414974464 281474602725080 281474602725211 281474602725211 281474602729420 0
See "man proc" for detail.
Fix spawn_spec.rb for Travis arm64 environment.
The process group id (/proc/[pid]/stat 5th field) is 0
in the Travis arm64 environment.
This is a case where it is available.
$ cat /proc/4543/stat
4543 (ruby) S 4525 4525 1384 34818 4525 4194304 37443 1754841 0 0 366 105 2291 391 20 0 3 0 1381328 1428127744 11475 18446744073709551615 94195983785984 94195986670225 140728933833312 0 0 0 0 0 1107394127 0 0 0 17 2 0 0 1 0 0 94195987686512 94195987708942 94196017770496 140728933835483 140728933835595 140728933835595 140728933842904 0
This is a case where it is not available in Travis arm64 environment.
$ cat /proc/19179/stat
19179 (ruby) S 19160 0 0 0 -1 4194560 37618 1710547 313 163 770 665 5206 1439 20 0 2 0 17529566 1196347392 10319 18446744073709551615 187650811428864 187650815023116 281474602721280 0 0 0 0 4096 1107390031 0 0 0 17 22 0 0 0 0 0 187650815091456 187650815114064 187651414974464 281474602725080 281474602725211 281474602725211 281474602729420 0
See "man proc" for detail.