当从python脚本调用时，为什么我的bash脚本不能从文件中读取行？

Question

I am trying to write a small program in bash and part of it needs to be able to get some values from a txt file where the different files are separated by a line, and then either add each line to a variable or add each line to one array.

So far I have tried this:

FILE=$"transfer_config.csv"
while read line
do
    MYARRAY[$index]="$line"
    index=$(($index+1))
done < $FILE
echo ${MYARRAY[0]}

This just produces a blank line though, and not what was on the first line of the config file.

I am not returned with any errors which is why I am not too sure why this is happening.

The bash script is called though a python script using os.system("$HOME/bin/mcserver_config/server_transfer/down/createRemoteFolder") , but if I simply call it after the python program has made the file which the bash script reads, it works.

I am almost 100% sure it is not an issue with the directories, because pwd at the top of the bash script shows it in the correct directory, and the python program is also creating the data file in the correct place.

Any help is much appreciated.

EDIT:

I also tried the subprocess.call("path_to_script", shell=True) to see if it would make a difference, I know it is unlikely but it didn't.

Answer 1

I suspect that when calling the bash script from python, having just created the file, you are not really finished with that file: you should either explicitly close the file or use a with construct.

Otherwise, the written data is still in any buffer (from the file object, or in the OS, or wherever). Only closing (or at least flushing) the file makes sure the data is indeed in the file.

BTW, instead of os.system , you should use the subprocess module...