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shell commands fail w/o notice ?

I'm quite confused with the Xterm interface on my Maemo5 N900 : It's there, it looks like a useful shell, but when I try to actually do something with it it behaves weirdly...

Consider this :

~/MyDocs/.documents $ ls -la myfile
-rw-r--r-- 1 user root 579498 Jan 6 02:14 myfile
~/MyDocs/.documents $ chmod 755 myfile
~/MyDocs/.documents $ ls -la myfile
-rw-r--r-- 1 user root 579498 Jan 6 02:14 myfile

Why is the file still non-executable ? And why did the shell not issue some kind of error ? I tried to
~/MyDocs/.documents $ sudo chmod 755 myfile
But that w/ the exact same result : Job not done and no error.

When I issue a "which chmod" I get a reassuring
/bin/chmod...

I'm obviously missing something, a week ago I tried to create a simple symlink but to no avail...

Please point me in the right direction, as for now I can't do much w/ the shell :(

Re: shell commands fail w/o notice ?

because you are in mydocs which is FAT32 you cannot do the same linux permission stuff there as you can with your linux partition.

Re: shell commands fail w/o notice ?

Arg ! This is happening to me all the time, I forgot wich FSystem I'm working on...! Thanks !

Re: shell commands fail w/o notice ?

Actually you can chmod files on the MyDocs partition, unless I am misunderstanding your problem. But every time I run into the problem you describe, I have to do a filesystemcheck because the superblock got corrupted, one way or another.

So, when I run into that problem, I unmount the MyDocs partition, fsck -a the now unmounted partition and remount after that.

Re: shell commands fail w/o notice ?

The mount options for /home/user/MyDocs specify noexec along with a fmask to ensure files are 644 (note dmask sets chmod 7777 for directories); see here:

Code:

~ $ grep MyDocs /etc/fstab 

/dev/mmcblk0p1 /home/user/MyDocs vfat noauto,nodev,noexec,nosuid,noatime,nodiratime,utf8,uid=29999,shortname=mixed,dmask=000,fmask=0133,rodir 0 0

~ $

You'll need to either:

a) Remove the noexec option and alter the fmask to force any file to be executable from with /etc/fstab (which is autogenerated, so this will need to be altered every time you boot?)

or

b) unmount manually /home/user/MyDocs and then manually remount with your preferred mount options.

Check the mount manpage for more details on mount options

http://linux.die.net/man/8/mount

There may be other threads on here regarding the specifics of fstab manipulation - give the search option a whirl.

Re: shell commands fail w/o notice ?

Quote:

Originally Posted by anthonie (Post 911383)

Are you subsequently mounting with defaults rather than the directives from fstab?

Re: shell commands fail w/o notice ?

Quote:

Originally Posted by gregoranderson (Post 911400)

Are you subsequently mounting with defaults rather than the directives from fstab?

Yesterday I had to chmod some files in a subdir from MyDocs. Experienced the same problems as OP, no error message from the terminal, but no changed file permissions either.

So, in order to get the job done, I did the following

Code:

sudo gainroot

umount /home/user/MyDocs

fsck -a /dev/mmcblk0p1

mount /home/user/MyDocs

That did the trick for me. Personally, I'd rather not change fstab entries, and even though I don't use Windows, I prefer maximum compatibility with OS's, so I kept the FAT32 as it is.

AFAIK, sh scripts can be run from a noexec partition. Binaries not.

So the answer is, yes, I use defaults.

Re: shell commands fail w/o notice ?

Thinking out loud, the only reason I can see you wanting to use the large partition for executables would be if you had ran out of room in /dev/mmcblk0p2 and wanted to store a large executable in there (although the original poster never stated any specific intentions).

If so, one solution would be to create a ext3 device with dd in /home/user/MyDocs/somewhere, and loopmount then add to your path. You can then symlink like a crazy mofo.

I'll use my mounted SD card just to be safe

Use DD to create a block device (in this case 500MB).

Code:

Nokia-N900:~# dd if=/dev/zero of=/media/mmc1/bigbin bs=1024 count=512000

512000+0 records in

512000+0 records out

Nokia-N900:~# ls -l /media/mmc1/

drwxrwxrwx    2 user     root        24576 Dec 31 23:30 DCIM

drwxrwxrwx   41 user     root         4096 Nov 20 23:02 Music

drwxrwxrwx    2 user     root         4096 Dec 31 16:47 Video

-rw-r--r--    1 user     root    524288000 Jan  4 13:01 bigbin

Use mkfs.ext3 to create a filesystem.

Code:

Nokia-N900:~# mkfs.ext3 /media/mmc1/bigbin 

mke2fs 1.41.3.maemo0 (12-Oct-2008)

/media/mmc1/bigbin is not a block special device.

Proceed anyway? (y,n) y

Filesystem label=

OS type: Linux

Block size=1024 (log=0)

Fragment size=1024 (log=0)

128016 inodes, 512000 blocks

25600 blocks (5.00%) reserved for the super user

First data block=1

Maximum filesystem blocks=67633152

63 block groups

8192 blocks per group, 8192 fragments per group

2032 inodes per group

Superblock backups stored on blocks: 

        8193, 24577, 40961, 57345, 73729, 204801, 221185, 401409



Writing inode tables: done                            

Creating journal (8192 blocks): done

Writing superblocks and filesystem accounting information: done



This filesystem will be automatically checked every 38 mounts or

180 days, whichever comes first.  Use tune2fs -c or -i to override.

Nokia-N900:~#

Create a mount point:

Code:

Nokia-N900:~# mkdir /home/user/bin

Nokia-N900:~# chown user:users /home/user/bin

And mount:

Code:

Nokia-N900:~# mount -o loop /media/mmc1/bigbin /home/user/bin

Create a script for the normal user:

Code:

Nokia-N900:~# su - user



BusyBox v1.10.2 (Debian 3:1.10.2.legal-1osso30+0m5) built-in shell (ash)

Enter 'help' for a list of built-in commands.



~ $ echo "date" > bin/test.sh ; chmod u+x bin/test.sh

And test:

Code:

~ $ PATH=$PATH:/home/user/bin

~ $ test.sh

Tue Jan  4 13:03:50 GMT 2011

Re: shell commands fail w/o notice ?

Interesting. I am on the verge of completely wiping my device for the first time since I got it, and I must admit your approach sounds tempting.

I might actually follow that path.

PS: Forgot to ask, are there any repercussions, removing the noexec paramater from fstab?