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-rw-r--r--doc/ChangeLog5
-rw-r--r--doc/gawk.110
-rw-r--r--doc/gawk.info731
-rw-r--r--doc/gawk.texi16
-rw-r--r--doc/gawktexi.in16
5 files changed, 407 insertions, 371 deletions
diff --git a/doc/ChangeLog b/doc/ChangeLog
index 854cad6d..da5ad1ad 100644
--- a/doc/ChangeLog
+++ b/doc/ChangeLog
@@ -48,6 +48,11 @@
* gawktexi.in (FN, FFN, DF,DDF, PVERSION, CTL): Remove macros.
They have no alternate versions and are just in the way.
+2013-08-15 Arnold D. Robbins <arnold@skeeve.com>
+
+ * gawk.1: Document that ENVIRON updates affect the environment.
+ * gawktexi.in: Ditto.
+
2013-06-27 Arnold D. Robbins <arnold@skeeve.com>
* texinfo.tex: Update from Karl, fixes a formating problem.
diff --git a/doc/gawk.1 b/doc/gawk.1
index 7f31c254..8d343024 100644
--- a/doc/gawk.1
+++ b/doc/gawk.1
@@ -13,7 +13,7 @@
. if \w'\(rq' .ds rq "\(rq
. \}
.\}
-.TH GAWK 1 "May 09 2013" "Free Software Foundation" "Utility Commands"
+.TH GAWK 1 "Aug 15 2013" "Free Software Foundation" "Utility Commands"
.SH NAME
gawk \- pattern scanning and processing language
.SH SYNOPSIS
@@ -917,11 +917,17 @@ An array containing the values of the current environment.
The array is indexed by the environment variables, each element being
the value of that variable (e.g., \fBENVIRON["HOME"]\fP might be
\fB"/home/arnold"\fR).
-Changing this array does not affect the environment seen by programs which
+.sp
+In POSIX mode,
+changing this array does not affect the environment seen by programs which
.I gawk
spawns via redirection or the
.B system()
function.
+Otherwise,
+.I gawk
+updates its real environment so that programs it spawns see
+the changes.
.TP
.B ERRNO
If a system error occurs either doing a redirection for
diff --git a/doc/gawk.info b/doc/gawk.info
index 24f08018..4e31aa3b 100644
--- a/doc/gawk.info
+++ b/doc/gawk.info
@@ -9688,9 +9688,18 @@ with a pound sign (`#').
An associative array containing the values of the environment.
The array indices are the environment variable names; the elements
are the values of the particular environment variables. For
- example, `ENVIRON["HOME"]' might be `/home/arnold'. Changing this
- array does not affect the environment passed on to any programs
- that `awk' may spawn via redirection or the `system()' function.
+ example, `ENVIRON["HOME"]' might be `/home/arnold'.
+
+ For POSIX `awk', changing this array does not affect the
+ environment passed on to any programs that `awk' may spawn via
+ redirection or the `system()' function.
+
+ However, beginning with version 4.2, if not in POSIX compatibility
+ mode, `gawk' does update its own environment when `ENVIRON' is
+ changed, thus changing the environment seen by programs that it
+ creates. You should therefore be especially careful if you modify
+ `ENVIRON["PATH"]"', which is the search path for finding
+ executable programs.
Some operating systems may not have environment variables. On
such systems, the `ENVIRON' array is empty (except for
@@ -30155,9 +30164,9 @@ Index
* dark corner, exit statement: Exit Statement. (line 30)
* dark corner, field separators: Field Splitting Summary.
(line 46)
-* dark corner, FILENAME variable <1>: Auto-set. (line 93)
+* dark corner, FILENAME variable <1>: Auto-set. (line 102)
* dark corner, FILENAME variable: Getline Notes. (line 19)
-* dark corner, FNR/NR variables: Auto-set. (line 314)
+* dark corner, FNR/NR variables: Auto-set. (line 323)
* dark corner, format-control characters: Control Letters. (line 18)
* dark corner, FS as null string: Single Character Fields.
(line 20)
@@ -30326,12 +30335,12 @@ Index
(line 23)
* differences in awk and gawk, close() function: Close Files And Pipes.
(line 81)
-* differences in awk and gawk, ERRNO variable: Auto-set. (line 73)
+* differences in awk and gawk, ERRNO variable: Auto-set. (line 82)
* differences in awk and gawk, error messages: Special FD. (line 16)
* differences in awk and gawk, FIELDWIDTHS variable: User-modified.
(line 35)
* differences in awk and gawk, FPAT variable: User-modified. (line 45)
-* differences in awk and gawk, FUNCTAB variable: Auto-set. (line 119)
+* differences in awk and gawk, FUNCTAB variable: Auto-set. (line 128)
* differences in awk and gawk, function arguments (gawk): Calling Built-in.
(line 16)
* differences in awk and gawk, getline command: Getline. (line 19)
@@ -30354,14 +30363,14 @@ Index
(line 261)
* differences in awk and gawk, print/printf statements: Format Modifiers.
(line 13)
-* differences in awk and gawk, PROCINFO array: Auto-set. (line 133)
+* differences in awk and gawk, PROCINFO array: Auto-set. (line 142)
* differences in awk and gawk, record separators: Records. (line 117)
* differences in awk and gawk, regexp constants: Using Constant Regexps.
(line 43)
* differences in awk and gawk, regular expressions: Case-sensitivity.
(line 26)
* differences in awk and gawk, RS/RT variables: Records. (line 172)
-* differences in awk and gawk, RT variable: Auto-set. (line 266)
+* differences in awk and gawk, RT variable: Auto-set. (line 275)
* differences in awk and gawk, single-character fields: Single Character Fields.
(line 6)
* differences in awk and gawk, split() function: String Functions.
@@ -30370,7 +30379,7 @@ Index
* differences in awk and gawk, strings, storing: Records. (line 191)
* differences in awk and gawk, strtonum() function (gawk): String Functions.
(line 406)
-* differences in awk and gawk, SYMTAB variable: Auto-set. (line 274)
+* differences in awk and gawk, SYMTAB variable: Auto-set. (line 283)
* differences in awk and gawk, TEXTDOMAIN variable: User-modified.
(line 162)
* differences in awk and gawk, trunc-mod operation: Arithmetic Ops.
@@ -30451,13 +30460,13 @@ Index
(line 11)
* EREs (Extended Regular Expressions): Bracket Expressions. (line 24)
* ERRNO variable <1>: TCP/IP Networking. (line 54)
-* ERRNO variable <2>: Auto-set. (line 73)
+* ERRNO variable <2>: Auto-set. (line 82)
* ERRNO variable <3>: BEGINFILE/ENDFILE. (line 26)
* ERRNO variable <4>: Close Files And Pipes.
(line 138)
* ERRNO variable: Getline. (line 19)
* error handling: Special FD. (line 16)
-* error handling, ERRNO variable and: Auto-set. (line 73)
+* error handling, ERRNO variable and: Auto-set. (line 82)
* error output: Special FD. (line 6)
* escape processing, gsub()/gensub()/sub() functions: Gory Details.
(line 6)
@@ -30569,7 +30578,7 @@ Index
* file names, distinguishing: Auto-set. (line 52)
* file names, in compatibility mode: Special Caveats. (line 9)
* file names, standard streams in gawk: Special FD. (line 46)
-* FILENAME variable <1>: Auto-set. (line 93)
+* FILENAME variable <1>: Auto-set. (line 102)
* FILENAME variable: Reading Files. (line 6)
* FILENAME variable, getline, setting with: Getline Notes. (line 19)
* filenames, assignments as: Ignoring Assigns. (line 6)
@@ -30636,9 +30645,9 @@ Index
* floating-point, numbers: General Arithmetic. (line 6)
* fnmatch extension function: Extension Sample Fnmatch.
(line 6)
-* FNR variable <1>: Auto-set. (line 103)
+* FNR variable <1>: Auto-set. (line 112)
* FNR variable: Records. (line 6)
-* FNR variable, changing: Auto-set. (line 314)
+* FNR variable, changing: Auto-set. (line 323)
* for statement: For Statement. (line 6)
* for statement, looping over arrays: Scanning an Array. (line 20)
* fork extension function: Extension Sample Fork.
@@ -30685,7 +30694,7 @@ Index
* FSF (Free Software Foundation): Manual History. (line 6)
* fts extension function: Extension Sample File Functions.
(line 77)
-* FUNCTAB array: Auto-set. (line 119)
+* FUNCTAB array: Auto-set. (line 128)
* function calls: Function Calls. (line 6)
* function calls, indirect: Indirect Calls. (line 6)
* function pointers: Indirect Calls. (line 6)
@@ -30754,7 +30763,7 @@ Index
* gawk, distribution: Distribution contents.
(line 6)
* gawk, ERRNO variable in <1>: TCP/IP Networking. (line 54)
-* gawk, ERRNO variable in <2>: Auto-set. (line 73)
+* gawk, ERRNO variable in <2>: Auto-set. (line 82)
* gawk, ERRNO variable in <3>: BEGINFILE/ENDFILE. (line 26)
* gawk, ERRNO variable in <4>: Close Files And Pipes.
(line 138)
@@ -30771,7 +30780,7 @@ Index
* gawk, FPAT variable in <1>: User-modified. (line 45)
* gawk, FPAT variable in: Splitting By Content.
(line 26)
-* gawk, FUNCTAB array in: Auto-set. (line 119)
+* gawk, FUNCTAB array in: Auto-set. (line 128)
* gawk, function arguments and: Calling Built-in. (line 16)
* gawk, hexadecimal numbers and: Nondecimal-numbers. (line 42)
* gawk, IGNORECASE variable in <1>: Array Sorting Functions.
@@ -30802,7 +30811,7 @@ Index
* gawk, OS/2 version of: PC Using. (line 11)
* gawk, PROCINFO array in <1>: Two-way I/O. (line 116)
* gawk, PROCINFO array in <2>: Time Functions. (line 47)
-* gawk, PROCINFO array in: Auto-set. (line 133)
+* gawk, PROCINFO array in: Auto-set. (line 142)
* gawk, regexp constants and: Using Constant Regexps.
(line 28)
* gawk, regular expressions, case sensitivity: Case-sensitivity.
@@ -30810,7 +30819,7 @@ Index
* gawk, regular expressions, operators: GNU Regexp Operators.
(line 6)
* gawk, regular expressions, precedence: Regexp Operators. (line 161)
-* gawk, RT variable in <1>: Auto-set. (line 266)
+* gawk, RT variable in <1>: Auto-set. (line 275)
* gawk, RT variable in <2>: Getline/Variable/File.
(line 10)
* gawk, RT variable in <3>: Multiple Line. (line 129)
@@ -30819,7 +30828,7 @@ Index
* gawk, source code, obtaining: Getting. (line 6)
* gawk, splitting fields and: Constant Size. (line 87)
* gawk, string-translation functions: I18N Functions. (line 6)
-* gawk, SYMTAB array in: Auto-set. (line 274)
+* gawk, SYMTAB array in: Auto-set. (line 283)
* gawk, TEXTDOMAIN variable in: User-modified. (line 162)
* gawk, timestamps: Time Functions. (line 6)
* gawk, uses for: Preface. (line 36)
@@ -31222,16 +31231,16 @@ Index
(line 47)
* nexti debugger command: Debugger Execution Control.
(line 49)
-* NF variable <1>: Auto-set. (line 108)
+* NF variable <1>: Auto-set. (line 117)
* NF variable: Fields. (line 33)
* NF variable, decrementing: Changing Fields. (line 107)
* ni debugger command (alias for nexti): Debugger Execution Control.
(line 49)
* noassign.awk program: Ignoring Assigns. (line 15)
* not Boolean-logic operator: Boolean Ops. (line 6)
-* NR variable <1>: Auto-set. (line 128)
+* NR variable <1>: Auto-set. (line 137)
* NR variable: Records. (line 6)
-* NR variable, changing: Auto-set. (line 314)
+* NR variable, changing: Auto-set. (line 323)
* null strings <1>: Basic Data Typing. (line 26)
* null strings <2>: Truth Values. (line 6)
* null strings <3>: Regexp Field Splitting.
@@ -31511,7 +31520,7 @@ Index
* PROCINFO array <3>: Group Functions. (line 6)
* PROCINFO array <4>: Passwd Functions. (line 6)
* PROCINFO array <5>: Time Functions. (line 47)
-* PROCINFO array <6>: Auto-set. (line 133)
+* PROCINFO array <6>: Auto-set. (line 142)
* PROCINFO array: Obsolete. (line 11)
* profiling awk programs: Profiling. (line 6)
* profiling awk programs, dynamically: Profiling. (line 172)
@@ -31665,7 +31674,7 @@ Index
* right angle bracket (>), >> operator (I/O): Redirection. (line 50)
* right shift, bitwise: Bitwise Functions. (line 32)
* Ritchie, Dennis: Basic Data Typing. (line 55)
-* RLENGTH variable: Auto-set. (line 253)
+* RLENGTH variable: Auto-set. (line 262)
* RLENGTH variable, match() function and: String Functions. (line 225)
* Robbins, Arnold <1>: Future Extensions. (line 6)
* Robbins, Arnold <2>: Bugs. (line 32)
@@ -31692,9 +31701,9 @@ Index
* RS variable: Records. (line 20)
* RS variable, multiline records and: Multiple Line. (line 17)
* rshift() function (gawk): Bitwise Functions. (line 52)
-* RSTART variable: Auto-set. (line 259)
+* RSTART variable: Auto-set. (line 268)
* RSTART variable, match() function and: String Functions. (line 225)
-* RT variable <1>: Auto-set. (line 266)
+* RT variable <1>: Auto-set. (line 275)
* RT variable <2>: Getline/Variable/File.
(line 10)
* RT variable <3>: Multiple Line. (line 129)
@@ -31777,7 +31786,7 @@ Index
(line 110)
* sidebar, Changing FS Does Not Affect the Fields: Field Splitting Summary.
(line 38)
-* sidebar, Changing NR and FNR: Auto-set. (line 312)
+* sidebar, Changing NR and FNR: Auto-set. (line 321)
* sidebar, Controlling Output Buffering with system(): I/O Functions.
(line 135)
* sidebar, Escape Sequences for Metacharacters: Escape Sequences.
@@ -31919,7 +31928,7 @@ Index
* substr() function: String Functions. (line 483)
* Sumner, Andrew: Other Versions. (line 64)
* switch statement: Switch Statement. (line 6)
-* SYMTAB array: Auto-set. (line 274)
+* SYMTAB array: Auto-set. (line 283)
* syntactic ambiguity: /= operator vs. /=.../ regexp constant: Assignment Ops.
(line 147)
* system() function: I/O Functions. (line 72)
@@ -32360,336 +32369,336 @@ Node: Built-in Variables403555
Node: User-modified404650
Ref: User-modified-Footnote-1413008
Node: Auto-set413070
-Ref: Auto-set-Footnote-1426148
-Ref: Auto-set-Footnote-2426353
-Node: ARGC and ARGV426409
-Node: Arrays430260
-Node: Array Basics431765
-Node: Array Intro432591
-Node: Reference to Elements436908
-Node: Assigning Elements439178
-Node: Array Example439669
-Node: Scanning an Array441401
-Node: Controlling Scanning443715
-Ref: Controlling Scanning-Footnote-1448638
-Node: Delete448954
-Ref: Delete-Footnote-1451719
-Node: Numeric Array Subscripts451776
-Node: Uninitialized Subscripts453959
-Node: Multidimensional455586
-Node: Multiscanning458678
-Node: Arrays of Arrays460267
-Node: Functions464907
-Node: Built-in465726
-Node: Calling Built-in466804
-Node: Numeric Functions468792
-Ref: Numeric Functions-Footnote-1472624
-Ref: Numeric Functions-Footnote-2472981
-Ref: Numeric Functions-Footnote-3473029
-Node: String Functions473298
-Ref: String Functions-Footnote-1496856
-Ref: String Functions-Footnote-2496985
-Ref: String Functions-Footnote-3497233
-Node: Gory Details497320
-Ref: table-sub-escapes498999
-Ref: table-sub-posix-92500353
-Ref: table-sub-proposed501704
-Ref: table-posix-sub503058
-Ref: table-gensub-escapes504603
-Ref: Gory Details-Footnote-1505779
-Ref: Gory Details-Footnote-2505830
-Node: I/O Functions505981
-Ref: I/O Functions-Footnote-1512966
-Node: Time Functions513113
-Ref: Time Functions-Footnote-1524046
-Ref: Time Functions-Footnote-2524114
-Ref: Time Functions-Footnote-3524272
-Ref: Time Functions-Footnote-4524383
-Ref: Time Functions-Footnote-5524495
-Ref: Time Functions-Footnote-6524722
-Node: Bitwise Functions524988
-Ref: table-bitwise-ops525550
-Ref: Bitwise Functions-Footnote-1529771
-Node: Type Functions529955
-Node: I18N Functions531106
-Node: User-defined532733
-Node: Definition Syntax533537
-Ref: Definition Syntax-Footnote-1538447
-Node: Function Example538516
-Node: Function Caveats541110
-Node: Calling A Function541531
-Node: Variable Scope542646
-Node: Pass By Value/Reference545609
-Node: Return Statement549117
-Node: Dynamic Typing552098
-Node: Indirect Calls553029
-Node: Library Functions562714
-Ref: Library Functions-Footnote-1566227
-Ref: Library Functions-Footnote-2566370
-Node: Library Names566541
-Ref: Library Names-Footnote-1570012
-Ref: Library Names-Footnote-2570232
-Node: General Functions570318
-Node: Strtonum Function571346
-Node: Assert Function574276
-Node: Round Function577602
-Node: Cliff Random Function579145
-Node: Ordinal Functions580161
-Ref: Ordinal Functions-Footnote-1583231
-Ref: Ordinal Functions-Footnote-2583483
-Node: Join Function583692
-Ref: Join Function-Footnote-1585463
-Node: Getlocaltime Function585663
-Node: Readfile Function589404
-Node: Data File Management591243
-Node: Filetrans Function591875
-Node: Rewind Function595944
-Node: File Checking597331
-Node: Empty Files598425
-Node: Ignoring Assigns600655
-Node: Getopt Function602208
-Ref: Getopt Function-Footnote-1613511
-Node: Passwd Functions613714
-Ref: Passwd Functions-Footnote-1622689
-Node: Group Functions622777
-Node: Walking Arrays630861
-Node: Sample Programs632998
-Node: Running Examples633672
-Node: Clones634400
-Node: Cut Program635624
-Node: Egrep Program645469
-Ref: Egrep Program-Footnote-1653242
-Node: Id Program653352
-Node: Split Program656968
-Ref: Split Program-Footnote-1660487
-Node: Tee Program660615
-Node: Uniq Program663418
-Node: Wc Program670847
-Ref: Wc Program-Footnote-1675113
-Ref: Wc Program-Footnote-2675313
-Node: Miscellaneous Programs675405
-Node: Dupword Program676593
-Node: Alarm Program678624
-Node: Translate Program683377
-Ref: Translate Program-Footnote-1687764
-Ref: Translate Program-Footnote-2688012
-Node: Labels Program688146
-Ref: Labels Program-Footnote-1691517
-Node: Word Sorting691601
-Node: History Sorting695485
-Node: Extract Program697324
-Ref: Extract Program-Footnote-1704827
-Node: Simple Sed704955
-Node: Igawk Program708017
-Ref: Igawk Program-Footnote-1723174
-Ref: Igawk Program-Footnote-2723375
-Node: Anagram Program723513
-Node: Signature Program726581
-Node: Advanced Features727681
-Node: Nondecimal Data729567
-Node: Array Sorting731150
-Node: Controlling Array Traversal731847
-Node: Array Sorting Functions740085
-Ref: Array Sorting Functions-Footnote-1743759
-Ref: Array Sorting Functions-Footnote-2743852
-Node: Two-way I/O744046
-Ref: Two-way I/O-Footnote-1749478
-Node: TCP/IP Networking749548
-Node: Profiling752392
-Node: Internationalization759889
-Node: I18N and L10N761314
-Node: Explaining gettext762000
-Ref: Explaining gettext-Footnote-1767068
-Ref: Explaining gettext-Footnote-2767252
-Node: Programmer i18n767417
-Node: Translator i18n771619
-Node: String Extraction772412
-Ref: String Extraction-Footnote-1773373
-Node: Printf Ordering773459
-Ref: Printf Ordering-Footnote-1776243
-Node: I18N Portability776307
-Ref: I18N Portability-Footnote-1778756
-Node: I18N Example778819
-Ref: I18N Example-Footnote-1781457
-Node: Gawk I18N781529
-Node: Debugger782150
-Node: Debugging783121
-Node: Debugging Concepts783554
-Node: Debugging Terms785410
-Node: Awk Debugging788007
-Node: Sample Debugging Session788899
-Node: Debugger Invocation789419
-Node: Finding The Bug790751
-Node: List of Debugger Commands797239
-Node: Breakpoint Control798573
-Node: Debugger Execution Control802237
-Node: Viewing And Changing Data805597
-Node: Execution Stack808953
-Node: Debugger Info810420
-Node: Miscellaneous Debugger Commands814402
-Node: Readline Support819578
-Node: Limitations820409
-Node: Arbitrary Precision Arithmetic822661
-Ref: Arbitrary Precision Arithmetic-Footnote-1824310
-Node: General Arithmetic824458
-Node: Floating Point Issues826178
-Node: String Conversion Precision827059
-Ref: String Conversion Precision-Footnote-1828764
-Node: Unexpected Results828873
-Node: POSIX Floating Point Problems831026
-Ref: POSIX Floating Point Problems-Footnote-1834851
-Node: Integer Programming834889
-Node: Floating-point Programming836628
-Ref: Floating-point Programming-Footnote-1842959
-Ref: Floating-point Programming-Footnote-2843229
-Node: Floating-point Representation843493
-Node: Floating-point Context844658
-Ref: table-ieee-formats845497
-Node: Rounding Mode846881
-Ref: table-rounding-modes847360
-Ref: Rounding Mode-Footnote-1850375
-Node: Gawk and MPFR850554
-Node: Arbitrary Precision Floats851809
-Ref: Arbitrary Precision Floats-Footnote-1854252
-Node: Setting Precision854568
-Ref: table-predefined-precision-strings855254
-Node: Setting Rounding Mode857399
-Ref: table-gawk-rounding-modes857803
-Node: Floating-point Constants858990
-Node: Changing Precision860419
-Ref: Changing Precision-Footnote-1861816
-Node: Exact Arithmetic861990
-Node: Arbitrary Precision Integers865128
-Ref: Arbitrary Precision Integers-Footnote-1868146
-Node: Dynamic Extensions868293
-Node: Extension Intro869751
-Node: Plugin License871016
-Node: Extension Mechanism Outline871701
-Ref: load-extension872118
-Ref: load-new-function873596
-Ref: call-new-function874591
-Node: Extension API Description876606
-Node: Extension API Functions Introduction877819
-Node: General Data Types882685
-Ref: General Data Types-Footnote-1888284
-Node: Requesting Values888583
-Ref: table-value-types-returned889314
-Node: Constructor Functions890268
-Node: Registration Functions893288
-Node: Extension Functions893973
-Node: Exit Callback Functions896198
-Node: Extension Version String897447
-Node: Input Parsers898097
-Node: Output Wrappers907854
-Node: Two-way processors912364
-Node: Printing Messages914572
-Ref: Printing Messages-Footnote-1915649
-Node: Updating `ERRNO'915801
-Node: Accessing Parameters916540
-Node: Symbol Table Access917770
-Node: Symbol table by name918282
-Node: Symbol table by cookie920029
-Ref: Symbol table by cookie-Footnote-1924159
-Node: Cached values924222
-Ref: Cached values-Footnote-1927671
-Node: Array Manipulation927762
-Ref: Array Manipulation-Footnote-1928860
-Node: Array Data Types928899
-Ref: Array Data Types-Footnote-1931602
-Node: Array Functions931694
-Node: Flattening Arrays935460
-Node: Creating Arrays942312
-Node: Extension API Variables947037
-Node: Extension Versioning947673
-Node: Extension API Informational Variables949574
-Node: Extension API Boilerplate950660
-Node: Finding Extensions954464
-Node: Extension Example955024
-Node: Internal File Description955754
-Node: Internal File Ops959845
-Ref: Internal File Ops-Footnote-1971353
-Node: Using Internal File Ops971493
-Ref: Using Internal File Ops-Footnote-1973846
-Node: Extension Samples974112
-Node: Extension Sample File Functions975636
-Node: Extension Sample Fnmatch984121
-Node: Extension Sample Fork985847
-Node: Extension Sample Inplace987065
-Node: Extension Sample Ord988843
-Node: Extension Sample Readdir989679
-Node: Extension Sample Revout991211
-Node: Extension Sample Rev2way991804
-Node: Extension Sample Read write array992494
-Node: Extension Sample Readfile994377
-Node: Extension Sample API Tests995195
-Node: Extension Sample Time995720
-Node: gawkextlib997084
-Node: Language History999844
-Node: V7/SVR3.11001366
-Node: SVR41003686
-Node: POSIX1005128
-Node: BTL1006514
-Node: POSIX/GNU1007248
-Node: Common Extensions1012783
-Node: Ranges and Locales1014089
-Ref: Ranges and Locales-Footnote-11018707
-Ref: Ranges and Locales-Footnote-21018734
-Ref: Ranges and Locales-Footnote-31018994
-Node: Contributors1019215
-Node: Installation1024290
-Node: Gawk Distribution1025184
-Node: Getting1025668
-Node: Extracting1026494
-Node: Distribution contents1028186
-Node: Unix Installation1033706
-Node: Quick Installation1034323
-Node: Additional Configuration Options1036767
-Node: Configuration Philosophy1038244
-Node: Non-Unix Installation1040598
-Node: PC Installation1041056
-Node: PC Binary Installation1042355
-Node: PC Compiling1044203
-Node: PC Testing1047147
-Node: PC Using1048323
-Node: Cygwin1052508
-Node: MSYS1053508
-Node: VMS Installation1054022
-Node: VMS Compilation1054625
-Ref: VMS Compilation-Footnote-11055632
-Node: VMS Installation Details1055690
-Node: VMS Running1057325
-Node: VMS Old Gawk1058932
-Node: Bugs1059406
-Node: Other Versions1063262
-Node: Notes1069346
-Node: Compatibility Mode1070146
-Node: Additions1070929
-Node: Accessing The Source1071856
-Node: Adding Code1073296
-Node: New Ports1079341
-Node: Derived Files1083476
-Ref: Derived Files-Footnote-11088797
-Ref: Derived Files-Footnote-21088831
-Ref: Derived Files-Footnote-31089431
-Node: Future Extensions1089529
-Node: Implementation Limitations1090106
-Node: Extension Design1091358
-Node: Old Extension Problems1092512
-Ref: Old Extension Problems-Footnote-11094020
-Node: Extension New Mechanism Goals1094077
-Ref: Extension New Mechanism Goals-Footnote-11097442
-Node: Extension Other Design Decisions1097628
-Node: Extension Future Growth1099734
-Node: Old Extension Mechanism1100570
-Node: Basic Concepts1102310
-Node: Basic High Level1102991
-Ref: figure-general-flow1103262
-Ref: figure-process-flow1103861
-Ref: Basic High Level-Footnote-11107090
-Node: Basic Data Typing1107275
-Node: Glossary1110630
-Node: Copying1136092
-Node: GNU Free Documentation License1173649
-Node: Index1198786
+Ref: Auto-set-Footnote-1426540
+Ref: Auto-set-Footnote-2426745
+Node: ARGC and ARGV426801
+Node: Arrays430652
+Node: Array Basics432157
+Node: Array Intro432983
+Node: Reference to Elements437300
+Node: Assigning Elements439570
+Node: Array Example440061
+Node: Scanning an Array441793
+Node: Controlling Scanning444107
+Ref: Controlling Scanning-Footnote-1449030
+Node: Delete449346
+Ref: Delete-Footnote-1452111
+Node: Numeric Array Subscripts452168
+Node: Uninitialized Subscripts454351
+Node: Multidimensional455978
+Node: Multiscanning459070
+Node: Arrays of Arrays460659
+Node: Functions465299
+Node: Built-in466118
+Node: Calling Built-in467196
+Node: Numeric Functions469184
+Ref: Numeric Functions-Footnote-1473016
+Ref: Numeric Functions-Footnote-2473373
+Ref: Numeric Functions-Footnote-3473421
+Node: String Functions473690
+Ref: String Functions-Footnote-1497248
+Ref: String Functions-Footnote-2497377
+Ref: String Functions-Footnote-3497625
+Node: Gory Details497712
+Ref: table-sub-escapes499391
+Ref: table-sub-posix-92500745
+Ref: table-sub-proposed502096
+Ref: table-posix-sub503450
+Ref: table-gensub-escapes504995
+Ref: Gory Details-Footnote-1506171
+Ref: Gory Details-Footnote-2506222
+Node: I/O Functions506373
+Ref: I/O Functions-Footnote-1513358
+Node: Time Functions513505
+Ref: Time Functions-Footnote-1524438
+Ref: Time Functions-Footnote-2524506
+Ref: Time Functions-Footnote-3524664
+Ref: Time Functions-Footnote-4524775
+Ref: Time Functions-Footnote-5524887
+Ref: Time Functions-Footnote-6525114
+Node: Bitwise Functions525380
+Ref: table-bitwise-ops525942
+Ref: Bitwise Functions-Footnote-1530163
+Node: Type Functions530347
+Node: I18N Functions531498
+Node: User-defined533125
+Node: Definition Syntax533929
+Ref: Definition Syntax-Footnote-1538839
+Node: Function Example538908
+Node: Function Caveats541502
+Node: Calling A Function541923
+Node: Variable Scope543038
+Node: Pass By Value/Reference546001
+Node: Return Statement549509
+Node: Dynamic Typing552490
+Node: Indirect Calls553421
+Node: Library Functions563106
+Ref: Library Functions-Footnote-1566619
+Ref: Library Functions-Footnote-2566762
+Node: Library Names566933
+Ref: Library Names-Footnote-1570404
+Ref: Library Names-Footnote-2570624
+Node: General Functions570710
+Node: Strtonum Function571738
+Node: Assert Function574668
+Node: Round Function577994
+Node: Cliff Random Function579537
+Node: Ordinal Functions580553
+Ref: Ordinal Functions-Footnote-1583623
+Ref: Ordinal Functions-Footnote-2583875
+Node: Join Function584084
+Ref: Join Function-Footnote-1585855
+Node: Getlocaltime Function586055
+Node: Readfile Function589796
+Node: Data File Management591635
+Node: Filetrans Function592267
+Node: Rewind Function596336
+Node: File Checking597723
+Node: Empty Files598817
+Node: Ignoring Assigns601047
+Node: Getopt Function602600
+Ref: Getopt Function-Footnote-1613903
+Node: Passwd Functions614106
+Ref: Passwd Functions-Footnote-1623081
+Node: Group Functions623169
+Node: Walking Arrays631253
+Node: Sample Programs633390
+Node: Running Examples634064
+Node: Clones634792
+Node: Cut Program636016
+Node: Egrep Program645861
+Ref: Egrep Program-Footnote-1653634
+Node: Id Program653744
+Node: Split Program657360
+Ref: Split Program-Footnote-1660879
+Node: Tee Program661007
+Node: Uniq Program663810
+Node: Wc Program671239
+Ref: Wc Program-Footnote-1675505
+Ref: Wc Program-Footnote-2675705
+Node: Miscellaneous Programs675797
+Node: Dupword Program676985
+Node: Alarm Program679016
+Node: Translate Program683769
+Ref: Translate Program-Footnote-1688156
+Ref: Translate Program-Footnote-2688404
+Node: Labels Program688538
+Ref: Labels Program-Footnote-1691909
+Node: Word Sorting691993
+Node: History Sorting695877
+Node: Extract Program697716
+Ref: Extract Program-Footnote-1705219
+Node: Simple Sed705347
+Node: Igawk Program708409
+Ref: Igawk Program-Footnote-1723566
+Ref: Igawk Program-Footnote-2723767
+Node: Anagram Program723905
+Node: Signature Program726973
+Node: Advanced Features728073
+Node: Nondecimal Data729959
+Node: Array Sorting731542
+Node: Controlling Array Traversal732239
+Node: Array Sorting Functions740477
+Ref: Array Sorting Functions-Footnote-1744151
+Ref: Array Sorting Functions-Footnote-2744244
+Node: Two-way I/O744438
+Ref: Two-way I/O-Footnote-1749870
+Node: TCP/IP Networking749940
+Node: Profiling752784
+Node: Internationalization760281
+Node: I18N and L10N761706
+Node: Explaining gettext762392
+Ref: Explaining gettext-Footnote-1767460
+Ref: Explaining gettext-Footnote-2767644
+Node: Programmer i18n767809
+Node: Translator i18n772011
+Node: String Extraction772804
+Ref: String Extraction-Footnote-1773765
+Node: Printf Ordering773851
+Ref: Printf Ordering-Footnote-1776635
+Node: I18N Portability776699
+Ref: I18N Portability-Footnote-1779148
+Node: I18N Example779211
+Ref: I18N Example-Footnote-1781849
+Node: Gawk I18N781921
+Node: Debugger782542
+Node: Debugging783513
+Node: Debugging Concepts783946
+Node: Debugging Terms785802
+Node: Awk Debugging788399
+Node: Sample Debugging Session789291
+Node: Debugger Invocation789811
+Node: Finding The Bug791143
+Node: List of Debugger Commands797631
+Node: Breakpoint Control798965
+Node: Debugger Execution Control802629
+Node: Viewing And Changing Data805989
+Node: Execution Stack809345
+Node: Debugger Info810812
+Node: Miscellaneous Debugger Commands814794
+Node: Readline Support819970
+Node: Limitations820801
+Node: Arbitrary Precision Arithmetic823053
+Ref: Arbitrary Precision Arithmetic-Footnote-1824702
+Node: General Arithmetic824850
+Node: Floating Point Issues826570
+Node: String Conversion Precision827451
+Ref: String Conversion Precision-Footnote-1829156
+Node: Unexpected Results829265
+Node: POSIX Floating Point Problems831418
+Ref: POSIX Floating Point Problems-Footnote-1835243
+Node: Integer Programming835281
+Node: Floating-point Programming837020
+Ref: Floating-point Programming-Footnote-1843351
+Ref: Floating-point Programming-Footnote-2843621
+Node: Floating-point Representation843885
+Node: Floating-point Context845050
+Ref: table-ieee-formats845889
+Node: Rounding Mode847273
+Ref: table-rounding-modes847752
+Ref: Rounding Mode-Footnote-1850767
+Node: Gawk and MPFR850946
+Node: Arbitrary Precision Floats852201
+Ref: Arbitrary Precision Floats-Footnote-1854644
+Node: Setting Precision854960
+Ref: table-predefined-precision-strings855646
+Node: Setting Rounding Mode857791
+Ref: table-gawk-rounding-modes858195
+Node: Floating-point Constants859382
+Node: Changing Precision860811
+Ref: Changing Precision-Footnote-1862208
+Node: Exact Arithmetic862382
+Node: Arbitrary Precision Integers865520
+Ref: Arbitrary Precision Integers-Footnote-1868538
+Node: Dynamic Extensions868685
+Node: Extension Intro870143
+Node: Plugin License871408
+Node: Extension Mechanism Outline872093
+Ref: load-extension872510
+Ref: load-new-function873988
+Ref: call-new-function874983
+Node: Extension API Description876998
+Node: Extension API Functions Introduction878211
+Node: General Data Types883077
+Ref: General Data Types-Footnote-1888676
+Node: Requesting Values888975
+Ref: table-value-types-returned889706
+Node: Constructor Functions890660
+Node: Registration Functions893680
+Node: Extension Functions894365
+Node: Exit Callback Functions896590
+Node: Extension Version String897839
+Node: Input Parsers898489
+Node: Output Wrappers908246
+Node: Two-way processors912756
+Node: Printing Messages914964
+Ref: Printing Messages-Footnote-1916041
+Node: Updating `ERRNO'916193
+Node: Accessing Parameters916932
+Node: Symbol Table Access918162
+Node: Symbol table by name918674
+Node: Symbol table by cookie920421
+Ref: Symbol table by cookie-Footnote-1924551
+Node: Cached values924614
+Ref: Cached values-Footnote-1928063
+Node: Array Manipulation928154
+Ref: Array Manipulation-Footnote-1929252
+Node: Array Data Types929291
+Ref: Array Data Types-Footnote-1931994
+Node: Array Functions932086
+Node: Flattening Arrays935852
+Node: Creating Arrays942704
+Node: Extension API Variables947429
+Node: Extension Versioning948065
+Node: Extension API Informational Variables949966
+Node: Extension API Boilerplate951052
+Node: Finding Extensions954856
+Node: Extension Example955416
+Node: Internal File Description956146
+Node: Internal File Ops960237
+Ref: Internal File Ops-Footnote-1971745
+Node: Using Internal File Ops971885
+Ref: Using Internal File Ops-Footnote-1974238
+Node: Extension Samples974504
+Node: Extension Sample File Functions976028
+Node: Extension Sample Fnmatch984513
+Node: Extension Sample Fork986239
+Node: Extension Sample Inplace987457
+Node: Extension Sample Ord989235
+Node: Extension Sample Readdir990071
+Node: Extension Sample Revout991603
+Node: Extension Sample Rev2way992196
+Node: Extension Sample Read write array992886
+Node: Extension Sample Readfile994769
+Node: Extension Sample API Tests995587
+Node: Extension Sample Time996112
+Node: gawkextlib997476
+Node: Language History1000236
+Node: V7/SVR3.11001758
+Node: SVR41004078
+Node: POSIX1005520
+Node: BTL1006906
+Node: POSIX/GNU1007640
+Node: Common Extensions1013175
+Node: Ranges and Locales1014481
+Ref: Ranges and Locales-Footnote-11019099
+Ref: Ranges and Locales-Footnote-21019126
+Ref: Ranges and Locales-Footnote-31019386
+Node: Contributors1019607
+Node: Installation1024682
+Node: Gawk Distribution1025576
+Node: Getting1026060
+Node: Extracting1026886
+Node: Distribution contents1028578
+Node: Unix Installation1034098
+Node: Quick Installation1034715
+Node: Additional Configuration Options1037159
+Node: Configuration Philosophy1038636
+Node: Non-Unix Installation1040990
+Node: PC Installation1041448
+Node: PC Binary Installation1042747
+Node: PC Compiling1044595
+Node: PC Testing1047539
+Node: PC Using1048715
+Node: Cygwin1052900
+Node: MSYS1053900
+Node: VMS Installation1054414
+Node: VMS Compilation1055017
+Ref: VMS Compilation-Footnote-11056024
+Node: VMS Installation Details1056082
+Node: VMS Running1057717
+Node: VMS Old Gawk1059324
+Node: Bugs1059798
+Node: Other Versions1063654
+Node: Notes1069738
+Node: Compatibility Mode1070538
+Node: Additions1071321
+Node: Accessing The Source1072248
+Node: Adding Code1073688
+Node: New Ports1079733
+Node: Derived Files1083868
+Ref: Derived Files-Footnote-11089189
+Ref: Derived Files-Footnote-21089223
+Ref: Derived Files-Footnote-31089823
+Node: Future Extensions1089921
+Node: Implementation Limitations1090498
+Node: Extension Design1091750
+Node: Old Extension Problems1092904
+Ref: Old Extension Problems-Footnote-11094412
+Node: Extension New Mechanism Goals1094469
+Ref: Extension New Mechanism Goals-Footnote-11097834
+Node: Extension Other Design Decisions1098020
+Node: Extension Future Growth1100126
+Node: Old Extension Mechanism1100962
+Node: Basic Concepts1102702
+Node: Basic High Level1103383
+Ref: figure-general-flow1103654
+Ref: figure-process-flow1104253
+Ref: Basic High Level-Footnote-11107482
+Node: Basic Data Typing1107667
+Node: Glossary1111022
+Node: Copying1136484
+Node: GNU Free Documentation License1174041
+Node: Index1199178

End Tag Table
diff --git a/doc/gawk.texi b/doc/gawk.texi
index 10486cea..ca07e753 100644
--- a/doc/gawk.texi
+++ b/doc/gawk.texi
@@ -13659,10 +13659,18 @@ it is not special.
An associative array containing the values of the environment. The array
indices are the environment variable names; the elements are the values of
the particular environment variables. For example,
-@code{ENVIRON["HOME"]} might be @file{/home/arnold}. Changing this array
-does not affect the environment passed on to any programs that
-@command{awk} may spawn via redirection or the @code{system()} function.
-@c (In a future version of @command{gawk}, it may do so.)
+@code{ENVIRON["HOME"]} might be @file{/home/arnold}.
+
+For POSIX @command{awk}, changing this array does not affect the
+environment passed on to any programs that @command{awk} may spawn via
+redirection or the @code{system()} function.
+
+However, beginning with version 4.2, if not in POSIX
+compatibility mode, @command{gawk} does update its own environment when
+@code{ENVIRON} is changed, thus changing the environment seen by programs
+that it creates. You should therefore be especially careful if you
+modify @code{ENVIRON["PATH"]"}, which is the search path for finding
+executable programs.
Some operating systems may not have environment variables.
On such systems, the @code{ENVIRON} array is empty (except for
diff --git a/doc/gawktexi.in b/doc/gawktexi.in
index 771ef1c4..839f22d7 100644
--- a/doc/gawktexi.in
+++ b/doc/gawktexi.in
@@ -13044,10 +13044,18 @@ it is not special.
An associative array containing the values of the environment. The array
indices are the environment variable names; the elements are the values of
the particular environment variables. For example,
-@code{ENVIRON["HOME"]} might be @file{/home/arnold}. Changing this array
-does not affect the environment passed on to any programs that
-@command{awk} may spawn via redirection or the @code{system()} function.
-@c (In a future version of @command{gawk}, it may do so.)
+@code{ENVIRON["HOME"]} might be @file{/home/arnold}.
+
+For POSIX @command{awk}, changing this array does not affect the
+environment passed on to any programs that @command{awk} may spawn via
+redirection or the @code{system()} function.
+
+However, beginning with version 4.2, if not in POSIX
+compatibility mode, @command{gawk} does update its own environment when
+@code{ENVIRON} is changed, thus changing the environment seen by programs
+that it creates. You should therefore be especially careful if you
+modify @code{ENVIRON["PATH"]"}, which is the search path for finding
+executable programs.
Some operating systems may not have environment variables.
On such systems, the @code{ENVIRON} array is empty (except for