Bonjour||soir.
Je comprends pas les syntaxes suivantes.
Extrait de la documentation bash : https://www.gnu.org/software/bash/manual/bash.html (3.5.3 Shell Parameter Expansion)
Put another way, if the colon is included, the operator tests for both parameter’s existence and that its value is not null; if the colon is omitted, the operator tests only for existence.
${parameter:-word}
If parameter is unset or null, the expansion of word is substituted. Otherwise, the value of parameter is substituted.# v=123 # echo ${v-unset} 123
${parameter:=word}
If parameter (…)