data <- read_fwf(paste0(wd, "/saisie/", fichiers[i]), fwf_positions(start = Long$Deb ,end = Long$Fin ), skip_empty_rows = TRUE, locale = locale(encoding = "UTF-8"))
when it find à special caracter like : ¨, é, ... it respectr not the width that I imposed in fwf_positions.

I tried : read.fwf whith widths = the width the variable , but the problem is I dont need to put the width because I have when it starts and when it finish , for exemple var1 : start= 1 fin=8, var2 : start=10, fin=12 , so it is not continued