[Solved] bash script saving to files

[Minty_64]

hello!

I have been using bash scripts I have made myself (rather simple ones) and I'm looking for, but haven't found an answer to, saving separate files each time a script is run.
like having; log 1, log 2, log 3.

I think I have encountered an answer before and lost how to translate it into bash, it's described as: if log file 1 exists then log file 2 would be created, so on and so forth.

[BlackVeils]

you could simply use a variable in the log file name with date (and time if needed), then it will always be a different name.

man date

my chosen layouts:

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date '+%d_%m_%Y'

date '+%a_%d_%b_%H.%M'

[Minty_64]

sorry for the late response
can you use that in an example?
like with 'touch'

[Habitual]

16.4. Text Processing Commands

You're either asking how the script can do this for you, or...
How to code shell scripts to write to log files?

via shell script:

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export LOG=/path/to/file.log
...
internal|external command >> $LOG

If log1 exists, write log2, etc.
you have to code for these requirements.
See "CONDITIONAL EXPRESSIONS" in

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man bash

[Habitual]

http://www.tldp.org/LDP/abs/html/index.html

[Habitual]

hello!

I have been using bash scripts I have made myself (rather simple ones) and I'm looking for, but haven't found an answer to, saving separate files each time a script is run.
like having; log 1, log 2, log 3.

I think I have encountered an answer before and lost how to translate it into bash, it's described as: if log file 1 exists then log file 2 would be created, so on and so forth.

for arbitrary commands you run and on-the-fly logging use:

Code: Select all

/path/to/my/script.sh &> filename.log

else, code for it.

[BlackVeils]

example of date command method for new log file name:

create the date command variable

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TIME=$(date '+%a_%d_%b_%H.%M')

call the variable named TIME like this

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/path/to/File_name_"$TIME".log

so the result would be something like this

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/path/to/File_name_Mon_18_May_18.18.log

[WharfRat]

Minty_64,

To get the log name you want incorporate this sample

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#!/bin/bash

d=0
while true ; do
    [ -e log.$d ] || break
    d=$(($d + 1))
done
echo Next log file would be": log.$d"
exit 0

Good luck

[Flemur]

Here's a script that downloads npr's "newscast.mp3" and saves it as unique files with the date:
"newscast.mp3" -> "npr_15.05.22_09.12.51.mp3"

Code: Select all

#
# now=$(date +%s )
now=$(date +%y.%m.%d_%H.%M.%S)
filename="npr_$now.mp3"
wget http://public.npr.org/anon.npr-mp3/npr/news/newscast.mp3  --output-document=$filename
#

[Pilosopong Tasyo]

...saving separate files each time a script is run. like having; log 1, log 2, log 3...

Add the following line in your script. Somewhere near the beginning should suffice:

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LOGFILENAME="$0".log"$(ls "$0"* | wc -l)"

When you want to send text to the logfile anywhere in your script, just redirect it to $LOGFILENAME. The next time you run the script, a new logfile will be used.

The above uses the script's file name for the basename, and .log1, .log2, .log3, et al. for the file extension. It's assumed the script's filename is unique in the folder where it's being run.

sample-script

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#!/usr/bin/env bash

LOGFILENAME="$0".log"$(ls "$0"* | wc -l)"

# Log some things
echo "$(date) - Lorem ipsum" >> "$LOGFILENAME"
# Something to do
echo "$(date) - dolor sit amet" >> "$LOGFILENAME"
# Something else to do
echo "$(date) - fun with shell scripts" >> "$LOGFILENAME"

With "sample-script" as file name, running it several times in a row should produce:

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administrator@dg31pr:~/Desktop$ ls
sample-script

administrator@dg31pr:~/Desktop$ ./sample-script 
administrator@dg31pr:~/Desktop$ ./sample-script 
administrator@dg31pr:~/Desktop$ ./sample-script 
administrator@dg31pr:~/Desktop$ ./sample-script 
administrator@dg31pr:~/Desktop$ ./sample-script 

administrator@dg31pr:~/Desktop$ ls
sample-script       sample-script.log2  sample-script.log4
sample-script.log1  sample-script.log3  sample-script.log5

administrator@dg31pr:~/Desktop$ cat sample-script.log5
Sat May 23 14:12:52 PHT 2015 - Lorem ipsum
Sat May 23 14:12:52 PHT 2015 - dolor sit amet
Sat May 23 14:12:52 PHT 2015 - fun with shell scripts

administrator@dg31pr:~/Desktop$

[Minty_64]

that's what I wanted to know Pilosopong Tasyo, thank you!