ref: de6284e0377e1c10f6249586df1a67311e9c5b2f
parent: df6ccd29820f4e51d15eff6dab3c62014e877550
author: Arnold D. Robbins <arnold@skeeve.com>
date: Sun Jan 19 15:37:33 EST 2020
Fix Issue 60; sub/gsub follow POSIX if POSIXLY_CORRECT in the environment.
--- a/FIXES
+++ b/FIXES
@@ -25,6 +25,11 @@
This file lists all bug fixes, changes, etc., made since the AWK book
was sent to the printers in August, 1987.
+January 19, 2020:
+ If POSIXLY_CORRECT is set in the environment, then sub and gsub
+ use POSIX rules for multiple backslashes. This fixes Issue #66,
+ while maintaining backwards compatibility.
+
January 9, 2020:
Input/output errors on closing files are now fatal instead of
mere warnings. Thanks to Martijn Dekker <martijn@inlv.org>.
--- a/awk.1
+++ b/awk.1
@@ -502,6 +502,16 @@
Parameters are local to the function; all other variables are global.
Thus local variables may be created by providing excess parameters in
the function definition.
+.SH ENVIRONMENT VARIABLES
+If
+.B POSIXLY_CORRECT
+is set in the environment, then
+.I awk
+follows the POSIX rules for
+.B sub
+and
+.B gsub
+with respect to consecutive backslashes and ampersands.
.SH EXAMPLES
.TP
.EX
--- a/main.c
+++ b/main.c
@@ -22,7 +22,7 @@
THIS SOFTWARE.
****************************************************************/
-const char *version = "version 20200109";
+const char *version = "version 20200119";
#define DEBUG
#include <stdio.h>
--- a/run.c
+++ b/run.c
@@ -1983,7 +1983,14 @@
{ /* sptr[0] == '\\' */char *pb = *pb_ptr;
const char *sptr = *sptr_ptr;
+ static bool first = true;
+ static bool do_posix = false;
+ if (first) {+ first = false;
+ do_posix = (getenv("POSIXLY_CORRECT") != NULL);+ }
+
if (sptr[1] == '\\') { if (sptr[2] == '\\' && sptr[3] == '&') { /* \\\& -> \& */*pb++ = '\\';
@@ -1992,6 +1999,9 @@
} else if (sptr[2] == '&') { /* \\& -> \ + matched */*pb++ = '\\';
sptr += 2;
+ } else if (do_posix) { /* \\x -> \x */+ sptr++;
+ *pb++ = *sptr++;
} else { /* \\x -> \\x */*pb++ = *sptr++;
*pb++ = *sptr++;
--
⑨