process table format ugly when kernel.pid_max > 99999

[Zugschlus]

This is me forwarding https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=850189

I run atop on a system where kernel.pid_max = 4194303.
Since all PIDs can be longer than 5 characters this leads to
an ugly jagged look in the process table once this happens:

   PID    TID  THR  SYSCPU USRCPU  VGROW   RGROW  RDDSK  WRDSK  ST EXC S  CPUNR  CPU CMD         1/6
1818110      -    1   0.12s  0.06s     0K      0K     0K     0K  --   - S      2   2% apps.plugin
1023550      -   10   0.02s  0.05s     0K      0K     0K     0K  --   - S      3   1% netdata
3885756      -   31   0.03s  0.01s     0K      0K     0K     0K  --   - S      0   0% mysqld
1023566      -    5   0.00s  0.04s     0K      0K     0K     0K  --   - S      3   0% python
1934013      -    1   0.03s  0.01s     0K      0K     0K     0K  --   - R      2   0% atop  
3950051      -    1   0.03s  0.01s     0K      0K     0K     0K  --   - S      0   0% gkrellmd
1917616      -    1   0.00s  0.02s     0K      0K     0K     0K  --   - S      0   0% bash
966886      -    1   0.00s  0.01s     0K      0K     0K     0K  --   - S      2   0% tor
303558      -   11   0.00s  0.01s     0K      0K     0K     0K  --   - S      1   0% syncthing
    38      -    1   0.01s  0.00s     0K      0K     0K     0K  --   - S      3   0% ksmd
1281656      -    7   0.00s  0.00s     0K      0K     0K     0K  --   - S      2   0% named
1167743      -    1   0.00s  0.00s     0K      0K     0K     0K  --   - S      2   0% php-fpm7.0
587618      -    7   0.00s  0.00s     0K      0K     0K     0K  --   - S      1   0% fail2ban-serve

This of course is only a minor cosmetic bug.
(To be fair, this is quite common upon tools displaying
PIDs, glances for example has the same problem.)

Thanks to Sven Hartge

[Atoptool]

This issue has been solved already by reading /proc/sys/kernel/pid_max during startup of atop to determine the maximum number of digits. Atop adapts the column width of both PIDs and TIDs accordingly.