Node:V7/SVR3.1, Next:SVR4, Previous:Language History, Up:Language History
The 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:
; to separate rules on a line
(see awk Statements Versus Lines).
return statement
(see User-Defined Functions).
delete statement (see The delete Statement).
do-while statement
(see The do-while Statement).
atan2, cos, sin, rand, and
srand (see Numeric Functions).
gsub, sub, and match
(see String Manipulation Functions).
close and system
(see Input/Output Functions).
ARGC, ARGV, FNR, RLENGTH, RSTART,
and SUBSEP built-in variables (see Built-in Variables).
?:
(see Conditional Expressions).
^
(see Arithmetic Operators) and its assignment operator
form ^= (see Assignment Expressions).
awk
programs (see Operator Precedence (How Operators Nest)).
FS
(see Specifying How Fields Are Separated) and as the
third argument to the split function
(see String Manipulation Functions).
~ and !~ operators
(see How to Use Regular Expressions).
\b, \f, and \r
(see Escape Sequences).
(Some vendors have updated their old versions of awk to
recognize \b, \f, and \r, but this is not
something you can rely on.)
getline function
(see Explicit Input with getline).
BEGIN and END rules
(see The BEGIN and END Special Patterns).