Data manipulation: 

#Select files_list

file_names <- list.files(getwd())

file_names <- file_names[grepl(".txt",file_names)]


#Initialize read.csv command

files <- read.csv("sobcov00.txt", header = F, stringsAsFactors = F, sep = "|")


#use lapply to append text files

files <- lapply(file_names, read.csv, header=F, stringsAsFactors = F, sep = "|")

files <- do.call(rbind,files)

files <- setNames(files, c("commyear","statecode", "abb","countycode","countyname","commcode",

                           "commname", "ip", "ipa","cc", "dt","cl","psc","pepc","pic","uepc", "uic",

                           "qt","nrq","compacres","la","tpa","sa","ia","lr"))

#write to stata

library(foreign)

write.dta(files, "main_data.dta")