awk language evolved considerably between the release of
Version 7 Unix (1978) and the new version that was first made generally available in
System V Release 3.1 (1987). This section summarizes the changes, with
cross-references to further details:
returnstatement (see User-defined).
deletestatement (see Delete).
whilestatement (see Do Statement).
srand()(see Numeric Functions).
match()(see String Functions).
system()(see I/O Functions).
SUBSEPbuilt-in variables (see Built-in Variables).
$0(see Changing Fields).
forstatements (see Reference to Elements).
awkprograms (see Precedence).
FS(see Field Separators) and as the third argument to the
split()function (see String Functions), rather than using only the first character of
awkto recognize ‘\b’, ‘\f’, and ‘\r’, but this is not something you can rely on.)
getlinefunction (see Getline).
ENDrules (see BEGIN/END).