[Bug-time] GNU Time 1.7.90 - usefulness of output

[Bruno Haible]

Hello,

Some of the values reported by 'time' should be marked as
"n/a" instead of 0. For example, on Linux:

$ ./time -v /tmp/clisp/build-porting32-gcc-safety0-optimized/clisp -x '(gc)'
...
        Command being timed: 
"/tmp/clisp/build-porting32-gcc-safety0-optimized/clisp -x (gc)"
        User time (seconds): 0.03
        System time (seconds): 0.00
        Percent of CPU this job got: 100%
        Elapsed (wall clock) time (h:mm:ss or m:ss): 0:00.04
        Average shared text size (kbytes): 0                            -- 
probably should be n/a
        Average unshared data size (kbytes): 0                  -- probably 
should be n/a
        Average stack size (kbytes): 0                                  -- 
probably should be n/a
        Average total size (kbytes): 0                                  -- 
probably should be n/a
        Maximum resident set size (kbytes): 5688
        Average resident set size (kbytes): 0                           -- 
probably should be n/a
        Major (requiring I/O) page faults: 0
        Minor (reclaiming a frame) page faults: 1229
        Voluntary context switches: 1
        Involuntary context switches: 2
        Swaps: 0
        File system inputs: 0
        File system outputs: 0
        Socket messages sent: 0
        Socket messages received: 0
        Signals delivered: 0                                                    
        -- definitely should be n/a (many SIGSEGVs not counted)
        Page size (bytes): 4096
        Exit status: 0

I know that the implementation of such a feature would be system dependent.
But it's a question of credibility to not output "0" for "unknown" or "n/a".

Bruno