每個進程會對應一個/proc下的一個目錄: /proc/進程ID

[root@www.netkiller.cn ~]# ls /proc/
1     122   1449  18    1891  1942  20    2306  2507  36    44   63   75  96           ioports       schedstat
10    123   1450  180   19    1943  2015  2308  2509  37    45   631  76  97           ipmi          scsi
100   124   1451  1802  190   1944  2016  2327  2519  38    46   632  77  976          irq           self
101   125   1452  182   1912  1945  203   2354  2521  3892  47   633  78  98           kallsyms      slabinfo
102   126   1453  1825  1921  1946  2057  2359  2526  3893  48   634  79  99           kcore         softirqs
103   127   1454  183   1922  1947  2060  2368  26    39    49   635  8   acpi         keys          stat
104   128   1455  184   1923  1948  2077  2370  27    3918  5    636  80  asound       key-users     swaps
105   129   1456  1843  1924  1949  2094  2372  2725  3966  50   637  81  buddyinfo    kmsg          sys
1057  13    1457  185   1925  1950  21    2395  2727  3980  51   638  82  bus          kpagecount    sysrq-trigger
106   1368  1458  1852  1926  1951  2109  24    2792  4     52   639  83  cgroups      kpageflags    sysvipc
107   14    1459  1858  1927  1952  2118  2465  28    40    53   64   84  cmdline      loadavg       timer_list
108   1437  146   186   1928  1953  2132  2466  2804  4056  532  65   85  cpuinfo      locks         timer_stats
109   1438  1460  187   1930  1954  2159  2467  2805  4085  54   66   86  crypto       mdstat        tty
11    1439  1461  188   1931  1955  22    2470  29    4087  544  67   87  devices      meminfo       uptime
110   1440  1462  1880  1932  1956  2218  2476  3     41    55   68   88  diskstats    misc          version
111   1441  1463  1881  1934  1957  2233  2489  30    42    56   69   89  dma          modules       vmallocinfo
112   1442  147   1882  1935  1958  2236  2493  31    43    57   7    9   driver       mounts        vmstat
113   1443  15    1883  1936  1959  2241  2495  3100  434   58   70   90  execdomains  mtd           zoneinfo
114   1444  1547  1884  1937  1962  2247  25    32    435   59   71   91  fb           mtrr
115   1445  16    1885  1938  1974  2251  2502  33    436   6    72   92  filesystems  net
116   1446  17    1886  1939  1985  2267  2503  3387  437   60   721  93  fs           pagetypeinfo
117   1447  177   1887  1940  1986  2293  2505  34    438   61   73   94  interrupts   partitions
12    1448  1786  189   1941  2     23    2506  35    439   62   74   95  iomem        sched_debug
		

[root@www.netkiller.cn ~]# ps ax | grep rsyslogd
 2076 ?        Sl     0:00 /sbin/rsyslogd -i /var/run/syslogd.pid -c 5
12774 pts/0    S+     0:00 grep rsyslogd

[root@www.netkiller.cn ~]# ls -l /proc/2076/fd
total 0
lrwx------ 1 root root 64 May  9 18:02 0 -> socket:[13103]
l-wx------ 1 root root 64 May  9 18:02 1 -> /var/log/messages
l-wx------ 1 root root 64 May  9 18:02 2 -> /var/log/cron
lr-x------ 1 root root 64 May  9 18:02 3 -> /proc/kmsg
l-wx------ 1 root root 64 May  9 18:02 4 -> /var/log/secure