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Author Another bask problem
Billy N. Patton

2004-08-03, 5:53 pm

From within my bash script I need to open a file that will have a uniqu
identifier.

/home/bpatton/.fleet_cmd_file.<id#>

When I did this in PERL I used the time function to return the time in
seconds
The ferl functions is described as
Returns the number of non-leap seconds since
whatever time the system considers to be the epoch
(that's 00:00:00, January 1, 1904 for Mac OS, and

It needs to be a unique number/name

--
___ _ ____ ___ __ __
/ _ )(_) / /_ __ / _ \___ _/ /_/ /____ ___
/ _ / / / / // / / ___/ _ `/ __/ __/ _ \/ _ \
/____/_/_/_/\_, / /_/ \_,_/\__/\__/\___/_//_/
/___/
Texas Instruments ASIC Circuit Design Methodlogy Group
Dallas, Texas, 214-480-4455, b-patton@ti.com
Martin Blume

2004-08-03, 5:53 pm

"Billy N. Patton" schrieb
> From within my bash script I need to open a file that will have a
> uniqu[e] identifier.
>
> /home/bpatton/.fleet_cmd_file.<id#>
>
> When I did this in PERL I used the time function to return the
> time in seconds
> The ferl functions is described as
> Returns the number of non-leap seconds since
> whatever time the system considers to be the epoch
> (that's 00:00:00, January 1, 1904 for Mac OS, and
>
> It needs to be a unique number/name
>

with GNU date: /home/bpatton/.fleet_cmd_file.`date +%s`
with bash /home/bpatton/.fleet_cmd_file.${RANDOM}

As for the uniqueness, this is left as an exercise to the reader.

HTH. YMMV.
Martin



William Park

2004-08-03, 5:53 pm

Billy N. Patton <b-patton@ti.com> wrote:
> From within my bash script I need to open a file that will have a uniqu
> identifier.
>
> /home/bpatton/.fleet_cmd_file.<id#>
>
> When I did this in PERL I used the time function to return the time in
> seconds
> The ferl functions is described as
> Returns the number of non-leap seconds since
> whatever time the system considers to be the epoch
> (that's 00:00:00, January 1, 1904 for Mac OS, and
>
> It needs to be a unique number/name


Use $$ which is PID, if you want uniqueness while machine is running.
If you want unique name in your filesystem, then
man mktemp
man tempfile
man date

--
William Park <opengeometry@yahoo.ca>
Open Geometry Consulting, Toronto, Canada
Peter Ammon

2004-08-03, 5:53 pm

Billy N. Patton wrote:
> From within my bash script I need to open a file that will have a uniqu
> identifier.
>
> /home/bpatton/.fleet_cmd_file.<id#>
>
> When I did this in PERL I used the time function to return the time in
> seconds
> The ferl functions is described as
> Returns the number of non-leap seconds since
> whatever time the system considers to be the epoch
> (that's 00:00:00, January 1, 1904 for Mac OS, and
>
> It needs to be a unique number/name
>


The time in seconds isn't guaranteed unique (what if you have two
instances of the script running, or the script executes twice within a
second, or the clock gets set back...)

Try uuidgen for something more unique and accessible via bash. A UUID
is usually made from a combination of the hardware MAC address, random
values, and a time value with better than one second resolution.

-Peter
Rich Grise

2004-08-22, 8:48 pm

Martin Blume wrote:

> "Billy N. Patton" schrieb
> with GNU date: /home/bpatton/.fleet_cmd_file.`date +%s`
> with bash /home/bpatton/.fleet_cmd_file.${RANDOM}
>
> As for the uniqueness, this is left as an exercise to the reader.
>

date +%G%j%k%m%S%N

:-)

Rich Grise

2004-08-22, 8:48 pm

Peter Ammon wrote:

> Billy N. Patton wrote:
>
> The time in seconds isn't guaranteed unique (what if you have two
> instances of the script running, or the script executes twice within a
> second, or the clock gets set back...)
>
> Try uuidgen for something more unique and accessible via bash. A UUID
> is usually made from a combination of the hardware MAC address, random
> values, and a time value with better than one second resolution.
>

So! That's where those Doze programmers get those stupid registry entry
values! ;-)

Cheers!
Rich

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