回声没有打印某些变量

Question

I'm having some problem with my code not printing certain variables even if the variables has a string in it.

$ dmisysname=$(sed -ne 148p ./3A47083/S09850724414683/002590F3851A.txt | awk -F '=' '{ print $2 }' | sed 's/ //')
$ dmibrdname=$(sed -ne 157p ./3A47083/S09850724414683/002590F3851A.txt | awk -F '=' '{ print $2 }' | sed 's/ //')
$ echo $dmisysname $dmibrdname

This should give me whatever inside $dmisysname and $dmibrdname, but the output displays this:

X9DRi-LN4+/X9DR3-LN4+

To make sure that the 2 variables have a string in it, I echo each variable individually.

$ echo $dmisysname

PIO-647R-6RLN4F+-ST031

$ echo $dmibrdname

X9DRi-LN4+/X9DR3-LN4+

Am I doing something wrong that has to do something with the print buffer or is there a bigger problem that I don't see?

Answer 1

Your input file was created under windows, and as such uses CRLF line terminations. This causes the output from bash under linux to be confused, relative to what is expected, as per @Lurker's useful explanation .

Use the dos2unix utility to fix your file:

$ dmisysname=$(sed -ne 148p ./3A47083/S09850724414683/002590F3851A.txt | awk -F '=' '{ print $2 }' | sed 's/ //')
$ dmibrdname=$(sed -ne 157p ./3A47083/S09850724414683/002590F3851A.txt | awk -F '=' '{ print $2 }' | sed 's/ //')
$ echo $dmisysname $dmibrdname
 X9DRi-LN4+/X9DR3-LN4+
$ dos2unix 3A47083/S09850724414683/002590F3851A.txtdos2unix: converting file 3A47083/S09850724414683/002590F3851A.txt to Unix format ...
$ dmisysname=$(sed -ne 148p ./3A47083/S09850724414683/002590F3851A.txt | awk -F '=' '{ print $2 }' | sed 's/ //')
$ dmibrdname=$(sed -ne 157p ./3A47083/S09850724414683/002590F3851A.txt | awk -F '=' '{ print $2 }' | sed 's/ //')
$ echo $dmisysname $dmibrdname
PIO-647R-6RLN4F+-ST031 X9DRi-LN4+/X9DR3-LN4+
$ 

I recreated a workable version of your file under Linux, then used unix2dos to format it as per windows. Then I am able to recreate your problem. Reverting it back using dos2unix fixes it.

Answer 2

Each of your variables ends in a carriage return ( \\r ). So what happens is both are echoed, but the second one overwrites the first.

I'll illustrate with the -e option:

$ echo -e "FOO\rBAR\r"
BAR

But both are being echoed. It's just that BAR is overwriting FOO :

$ echo -e "FOO\rBAR\r" | od -c
0000000   F   O   O  \r   B   A   R  \r  \n
0000011