Shell Programming and Scripting

OK, I'm striving to abide by all the rules this time.

Here is a fragment of my windows10/cygwin64/bash script:

Code:

export BUPLOG=$(BackupRecords --log "$src")
robocopy  $(BackupRecords -mrbd "$src" --path "$src")  $(BackupRecords --appSwitches "$src") "$src" "$dst"  $(BackupRecords --fileSwitches "$src") >$BUPLOG 2>&1
BackupRecords --complete "$src"
echo \*\*\* ALL DONE \*\*\* >>$BUPLOG 2>&1

"BackupRecords --log" is a program I wrote to return a unique log file name using the current time.

The problem is that I get two different log files. How can I force the evaluation of BUGLOG sooner?


Thanks
Siegfried

What two log files do you get?

Show us the source for your BackupRecords program. Do you really need to invoke BackupRecords five times in a four line script?

How can you have two file names? You're calling "BackupRecords --log" just once and then use the shell variable, which is not modified in between.
Do other "BackupRecords --xxx" calls have side effects?

Even if running BackupRecords has side effects, all invocations are in subshell environments (so, except for the first invocation of BackupRecords, they shouldn't be able to affect he value of the BUPLOG variable in the invoking script). The only thing that makes sense to me is that value returned by BackupRecords --log must return a string that includes a command substitution (from the description, probably including an invocation of the date utility) that produces different results each time $BUPLOG is expanded. But, the only way to know for sure is to see the source for BackupRecords.

Yes! As I you inferred: $(BackupRecords --log) very similar to $(date +'%Y %b %d %H:%M:%ss'). If I call it too often, I get different log files (which is usually what I want).

However, in this case, I want the same log file for multiple uses within the same script. How can I evaluate $(BackupRecords --log) only once at the beginning of my script once and use it multiple times later in the script?

Thanks
Siegfried

I agree with the others in that the answer lies somewhere in your BackupRecords script...

Why don't you keep using BUPLOG all over, then?