Allow 'list' while backup is in progress

[fukawi2]

I've written a script to monitor the last archive timestamp (eg, with Nagios etc): https://github.com/fukawi2/check_attic

Unfortunately it looks like attic takes a lock on the file config when running list -- this means my script can't succeed within timeout periods while a backup is in progress, and I get text messages every 3 hours ;)

Here's the strace from attic list while attic create is in progress:

open("/mnt/bup/mail.attic/config", O_RDWR) = 4
ioctl(4, FIOCLEX)                       = 0
fstat(4, {st_mode=S_IFREG|0644, st_size=148, ...}) = 0
ioctl(4, SNDCTL_TMR_TIMEBASE or TCGETS, 0x7fffee168fc0) = -1 ENOTTY (Inappropriate ioctl for device)
fstat(4, {st_mode=S_IFREG|0644, st_size=148, ...}) = 0
lseek(4, 0, SEEK_CUR)                   = 0
brk(0xb5d000)                           = 0xb5d000
lseek(4, 0, SEEK_CUR)                   = 0
ioctl(4, SNDCTL_TMR_TIMEBASE or TCGETS, 0x7fffee168f10) = -1 ENOTTY (Inappropriate ioctl for device)
lseek(4, 0, SEEK_CUR)                   = 0
fcntl(4, F_SETLKW, {type=F_RDLCK, whence=SEEK_SET, start=0, len=0}^C

Can we perhaps not lock files if we're performing a read-only operation (like list)?

[mappu]

Seems sensible, +1

But can't you just check the mtime of the attic repository? The hints/index files seem to have the right timestamp for my most recent backup jobs.

Although i suppose checking the mtime would give a false positive for an interrupted job...

[fukawi2]

That was my original plan, however that won't work when the repository is remote and the check script doesn't have direct access to the filesystem. Plus the shortcoming you mentioned of not detecting an interrupted backup.

+1 also suffering this issue with Fukawi2's script.

[devZer0]

list command seems to block until backup is finished. at least it should tell that there is an operation in progress instead of silently doing nothing