How to read lines from a file into an array?
13,956
Solution 1
#!/bin/zsh
zmodload zsh/mapfile
FNAME=/path/to/some/file.txt
FLINES=( "${(f)mapfile[$FNAME]}" )
LIST="${mapfile[$FNAME]}" # Not required unless stuff uses it
integer POS=1 # Not required unless stuff uses it
integer SIZE=$#FLINES # Number of lines, not required unless stuff uses it
for ITEM in $FLINES
# Do stuff
(( POS++ ))
done
You have some strange things in your code:
- Why are you splitting
LIST
each time instead of making it an array variable? It is just a waste of CPU time. - Why don’t you use
for ITEM in ${(f)LIST}
? - There is a possibility to directly ask zsh about array length:
$#ARRAY
. No need in determining the index of the last occurrence of the last element. POS
gets the same value asSIZE
in your code. Hence it will iterate only once.- Brackets are problems likely because of 3.:
(I)
is matching against a pattern. Do read documentation.
Solution 2
I know it's been a lot of time since the question was answered but I think it's worth posting a simpler answer (which doesn't require the zsh/mapfile external module):
#!/bin/zsh
for line in "${(@f)"$(</path/to/some/file.txt)"}"
{
// do something with each $line
}
Author by
Robbie
Updated on June 22, 2022Comments
-
Robbie almost 2 years
I'm trying to read in a file as an array of lines and then iterate over it with zsh. The code I've got works most of the time, except if the input file contains certain characters (such as brackets). Here's a snippet of it:
#!/bin/zsh LIST=$(cat /path/to/some/file.txt) SIZE=${${(f)LIST}[(I)${${(f)LIST}[-1]}]} POS=${${(f)LIST}[(I)${${(f)LIST}[-1]}]} while [[ $POS -le $SIZE ]] ; do ITEM=${${(f)LIST}[$POS]} # Do stuff ((POS=POS+1)) done
What would I need to change to make it work properly?