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    SubjectRFC: Inconsistent short read behaviour in __do_proc_dointvec vs _proc_do_string
    Should repeated short reads in __do_proc_dointvec behave consistently with _proc_do_string ?

    Consider:

    > char c[1];
    > int n;
    >
    > while (1)
    > {
    > n = read(0, c, 1);
    >
    > if (n <= 0) break;
    >
    > write (1, c, 1);
    > }

    Running this program on /proc/self/stat emits the expected output.

    Running this program on /proc/sys/kernel/random/poolsize does not :-(

    The issue is that __do_proc_dointvec does not accommodate non-zero file positions
    when reading:

    > if (!tbl_data || !table->maxlen || !*lenp || (*ppos && !write)) {
    > *lenp = 0;
    > return 0;
    > }


    OTOH _proc_do_string seems quite willing to accommodate it:

    > if (write) {
    > ...
    > } else {
    > len = strlen(data);
    > if (len > maxlen)
    > len = maxlen;
    >
    > if (*ppos > len) {
    > *lenp = 0;
    > return 0;
    > }


    Should __do_proc_intvec behave more like _proc_do_string, or vice-versa ?


    Earl




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