Reading a portion of a file

[attn.steven.kuo at gmail.com]

On Mar 8, 10:35 am, cmfvulcan... at gmail.com wrote:

(snipped)


>
> Ok, regex was my first thought because I used to use grep with Perl
> and shell scripting to grab everything from one pattern to another
> pattern. The file is just an unformatted file. What is below is
> exactly what is in the file. There are no spaces between the beginning
> and ending tags and the content. Would you recommend using spaces
> there? And if so, why?
>
> A sample of the file:


You can use iterators:

import StringIO
import itertools

def group(line):
    if line[-6:-1] == 'START':
        group.current = group.current + 1
    return group.current

group.current = 0

data = """
#VS:COMMAND:df:START
Filesystem           1K-blocks      Used Available Use% Mounted on
/dev/vzfs             20971520    517652  20453868   3% /
tmpfs                  2016032        44   2015988   1% /var/run
tmpfs                  2016032         0   2016032   0% /var/lock
tmpfs                  2016032         0   2016032   0% /dev/shm
tmpfs                  2016032        44   2015988   1% /var/run
tmpfs                  2016032         0   2016032   0% /var/lock
#VS:COMMAND:df:STOP

#VS:FILE:/proc/loadavg:START
0.00 0.00 0.00 1/32 14543
#VS:FILE:/proc/loadavg:STOP

#VS:FILE:/proc/meminfo:START
MemTotal:       524288 kB
MemFree:        450448 kB
Buffers:             0 kB
Cached:              0 kB
SwapCached:          0 kB
Active:              0 kB
Inactive:            0 kB
HighTotal:           0 kB
HighFree:            0 kB
LowTotal:       524288 kB
LowFree:        450448 kB
SwapTotal:           0 kB
SwapFree:            0 kB
Dirty:               0 kB
Writeback:           0 kB
Mapped:          73840 kB
Slab:                0 kB
CommitLimit:         0 kB
Committed_AS:   248704 kB
PageTables:          0 kB
VmallocTotal:        0 kB
VmallocUsed:         0 kB
VmallocChunk:        0 kB
#VS:FILE:/proc/meminfo:STOP

#VS:FILE:/proc/stat:START
cpu  67188 0 26366 391669264 656686 0 0
cpu0 24700 0 10830 195807826 373309 0 0
cpu1 42488 0 15536 195861438 283376 0 0
intr 0
swap 0 0
ctxt 18105366807
btime 1171391058
processes 26501285
procs_running 1
procs_blocked 0
#VS:FILE:/proc/stat:STOP

#VS:FILE:/proc/uptime:START
1962358.88 1577059.05
#VS:FILE:/proc/uptime:STOP
""".lstrip("\n");

fh = StringIO.StringIO(data)

sections = itertools.groupby(itertools.ifilter(lambda line: len(line)
> 1, fh),
        lambda line: group(line))

for key, section in sections:
    for line in section:
        print key, line,


--
Hope this helps,
Steven