cat with loop can't read long lines [duplicate] - bash

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Read a file line by line assigning the value to a variable [duplicate]
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I just assigned a variable, but echo $variable shows something else
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Closed 4 years ago.
I have a problem with my script. I tried to read a xml file with cat and read each lines with a loop. For example:
cat file.xml | while read line; do echo $line done
But inside my xml files, i had very long lines without backslash and it seems like cat file.xml didn't take big lines on file. However, when i did cat file.xml without the 'while read line', it works.
Is cat limited by the length of the line? Or did i just do a bad manipulation? What should i do to get these lines?
Thanks and bye.
Here is my script that does not work (in french):
#!/bin/bash
## SCRIPT PERMETTANT DE POUVOIR PRENDRE UNE SOURCE DE TXT POSSEDANT DU TEXTE À CHAQUE LIGNE ET LES PLACER, GRACE À UN MOT CLEF, DANS DES FICHIERS SPECIFIES VIA LE CHEMIN D'ACCESS D'UN FOLDER INDIQUÉ PAR L'UTILISATEUR.
## EXEMPLE ##
## L'utilisateur prend un dossier "X" ou sont contenus des XML. Il a placé dans tous ces XML un mot clé "motclefnumero1". Grace à ce script, il pourra changer ce mot clé par les lignes d'un fichier texte.
#### DEMANDE UTILISATEUR ####
echo 'Quel est le fichier source TXT (Possedant ce que vous voulez mettre)'
read textSource
echo 'Quel est le folder où les fichiers que vous souhaitez traiter sont placés?'
read folderSource
echo 'Indiquer le mot clé souhaité (Exemple : motclef1)'
read motClef
# cat file | cut -c1-80
# TABLEAU CONTENANT LES LIGNES DE NOTRE SOURCE TXT
myArray=()
while IFS= read -r line; do
myArray+=("$line")
done < "$textSource"
i=0
## PROCESS
ls -1 "$folderSource" | while read file; do
cat "$folderSource/$file" | while read texte; do
# Dans le cas où le dossier folderSource n'existe pas
if [ ! -d "$folderSource/resultat" ]; then
mkdir "$folderSource/resultat"
fi
## Effectuer la transputation du texte demandé dans notre texte de remplacement
echo ${texte//$motClef/${myArray[$i]}} >> "$folderSource/resultat/$file"
echo "Line $i : $texte"
## CONSOLE LOG
echo ${myArray[$i]} $folderSource/$file
echo $i
done
## Increment i var
i=$((i+1))
done
RESOLVED :
Hello, i've resolved my problem. Instead of use this :
cat "$folderSource/$file" | while read texte; do
Just use IFS to read each line, it works :
while IFS='' read -r texte || [[ -n "$texte" ]]; do
done < "$folderSource/$file"