Warning: preg_match(): Compilation failed: group name must start with a non-digit at offset 8 in /sdb/e/8/system.co/includes/MagicWord.php on line 722

Warning: preg_match(): Compilation failed: group name must start with a non-digit at offset 8 in /sdb/e/8/system.co/includes/MagicWord.php on line 722

Warning: preg_match_all(): Compilation failed: group name must start with a non-digit at offset 4 in /sdb/e/8/system.co/includes/MagicWord.php on line 700

Warning: Invalid argument supplied for foreach() in /sdb/e/8/system.co/includes/MagicWord.php on line 701

Warning: preg_replace(): Compilation failed: group name must start with a non-digit at offset 4 in /sdb/e/8/system.co/includes/MagicWord.php on line 705

Warning: preg_match_all(): Compilation failed: group name must start with a non-digit at offset 4 in /sdb/e/8/system.co/includes/MagicWord.php on line 700

Warning: Invalid argument supplied for foreach() in /sdb/e/8/system.co/includes/MagicWord.php on line 701

Warning: preg_replace(): Compilation failed: group name must start with a non-digit at offset 4 in /sdb/e/8/system.co/includes/MagicWord.php on line 705

Warning: preg_match_all(): Compilation failed: group name must start with a non-digit at offset 4 in /sdb/e/8/system.co/includes/MagicWord.php on line 700

Warning: Invalid argument supplied for foreach() in /sdb/e/8/system.co/includes/MagicWord.php on line 701

Warning: preg_replace(): Compilation failed: group name must start with a non-digit at offset 4 in /sdb/e/8/system.co/includes/MagicWord.php on line 705

Warning: preg_match_all(): Compilation failed: group name must start with a non-digit at offset 4 in /sdb/e/8/system.co/includes/MagicWord.php on line 700

Warning: Invalid argument supplied for foreach() in /sdb/e/8/system.co/includes/MagicWord.php on line 701

Warning: preg_replace(): Compilation failed: group name must start with a non-digit at offset 4 in /sdb/e/8/system.co/includes/MagicWord.php on line 705

Warning: preg_match(): Compilation failed: group name must start with a non-digit at offset 8 in /sdb/e/8/system.co/includes/MagicWord.php on line 722

Warning: preg_match(): Compilation failed: group name must start with a non-digit at offset 8 in /sdb/e/8/system.co/includes/MagicWord.php on line 722

Warning: preg_match(): Compilation failed: group name must start with a non-digit at offset 8 in /sdb/e/8/system.co/includes/MagicWord.php on line 722

Warning: preg_match(): Compilation failed: group name must start with a non-digit at offset 8 in /sdb/e/8/system.co/includes/MagicWord.php on line 722

Warning: preg_match(): Compilation failed: group name must start with a non-digit at offset 8 in /sdb/e/8/system.co/includes/MagicWord.php on line 722
Variables bash - system.co.free.fr

Variables bash

De system.co.free.fr.
(Variables bash)
Ligne 146 : Ligne 146 :
</pre>
</pre>
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=chercher et remplacer dans une variable=
+
=chercher et remplacer une sous-chaîne dans une variable=
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+
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Bash propose aussi 4 types de remplacement dans le contenu des variables.
+
-
Ces remplacements peuvent se faire sur la première occurrence trouvée, ou sur toutes les occurrences. Les syntaxes suivantes gèrent respectivement ces deux cas :
+
-
 
+
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${VAR/recherche/remplacement} # première occurrence
+
-
${VAR//recherche/remplacement} # toutes les occurrences
+
-
 
+
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Dans tous les cas, c'est le morceau le plus grand correspondant à "recherche" qui sera remplacé. Ainsi, on aura :
+
 +
Il y a 2 possibilités: la première occurrence ou toutes les occurrences:
 +
<pre>
 +
${VAR/recherche/remplacé par} # première occurrence
 +
${VAR//recherche/remplacé par} # toutes les occurrences
 +
</pre>
 +
</br>
 +
Dans tous les cas, c'est la sous-chaîne la plus grande correspondant à "recherche" qui sera remplacée. <br>
 +
<pre>
VAR=abcABC123ABCabc
VAR=abcABC123ABCabc
-
echo ${VAR/b*c/Z} # aZ
+
echo ${VAR/b*c/Z}
 +
</pre>
 +
<pre>
 +
aZ
 +
</pre>
On peut aussi viser spécifiquement le début ou la fin d'une chaîne :
On peut aussi viser spécifiquement le début ou la fin d'une chaîne :
Ligne 208 : Ligne 212 :
echo ${VAR?pas definie} # rien, valeur nulle autorisée
echo ${VAR?pas definie} # rien, valeur nulle autorisée
echo ${VAR:?valeur nulle} # -bash: VAR: pas definie (sur stderr)
echo ${VAR:?valeur nulle} # -bash: VAR: pas definie (sur stderr)
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Bon, j'ai conscience que cela est plutôt indigeste, n'hésitez pas à poser vos questions et faire part de vos remarques.
 

Version du 17 octobre 2020 à 16:01

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