[uClibc] /proc/self/maps

[Allan Clark]

Matthieu it wrote:

>Hello, 
>
>I am using uclibc, and I would like to understand the informations
>given in /proc/self/maps :
>
>cat /proc/self/maps 
>00400000-00480000 r-xp 00000000 1f:01 911368     /bin/busybox
>10000000-10003000 rw-p 00080000 1f:01 911368     /bin/busybox
>10003000-1000d000 rwxp 00000000 00:00 0
>2aaa8000-2aaae000 r-xp 00000000 1f:01 1518164    /lib/ld-uClibc.so.0
>2aaae000-2aaaf000 rw-p 00000000 00:00 0
>2aaed000-2aaee000 rw-p 00005000 1f:01 1518164    /lib/ld-uClibc.so.0
>2aaee000-2aaf1000 r-xp 00000000 1f:01 1656580    /lib/libcrypt.so.0
>2aaf1000-2ab30000 ---p 00003000 00:00 0
>2ab30000-2ab31000 rw-p 00002000 1f:01 1656580    /lib/libcrypt.so.0
>2ab31000-2ab43000 rw-p 00000000 00:00 0
>2ab43000-2ab81000 r-xp 00000000 1f:01 1541936    /lib/libc.so.0
>2ab81000-2abc0000 ---p 0003e000 00:00 0
>2abc0000-2abc3000 rw-p 0003d000 1f:01 1541936    /lib/libc.so.0
>2abc3000-2abc5000 rw-p 00000000 00:00 0
>7fff5000-7fff8000 rwxp ffffe000 00:00 0
>
>
>I wonder what the "---p" maps are. Do they count in the actual memory
>used by the process ?
>
It's a page-marking: (linux-2.6.8/fs/proc/task_mmu.c at 94)

>         seq_printf(m, "%08lx-%08lx %c%c%c%c %08lx %02x:%02x %lu %n",
>                         map->vm_start,
>                         map->vm_end,
>                         flags & VM_READ ? 'r' : '-',
>                         flags & VM_WRITE ? 'w' : '-',
>                         flags & VM_EXEC ? 'x' : '-',
>                         flags & VM_MAYSHARE ? 's' : 'p',
>                         map->vm_pgoff << PAGE_SHIFT,
>                         MAJOR(dev), MINOR(dev), ino, &len);

Seems to mean "!sharable" ie private.  Not completely sure, just 
grepping for you.  Anyone feel to second the guess?

Allan