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[SCM] gawk branch, gawk-5.1-stable, updated. gawk-4.1.0-4160-g5ee5884
|
From: |
Arnold Robbins |
|
Subject: |
[SCM] gawk branch, gawk-5.1-stable, updated. gawk-4.1.0-4160-g5ee5884 |
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Date: |
Thu, 29 Oct 2020 04:04:24 -0400 (EDT) |
This is an automated email from the git hooks/post-receive script. It was
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the project "gawk".
The branch, gawk-5.1-stable has been updated
via 5ee58847061487a0fa9aa5ce0492cd4afb7aaa72 (commit)
from 8608b22db74694ee79253e8ed41d064fd4523637 (commit)
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- Log -----------------------------------------------------------------
http://git.sv.gnu.org/cgit/gawk.git/commit/?id=5ee58847061487a0fa9aa5ce0492cd4afb7aaa72
commit 5ee58847061487a0fa9aa5ce0492cd4afb7aaa72
Author: Arnold D. Robbins <arnold@skeeve.com>
Date: Wed Oct 28 20:13:08 2020 +0200
Add some doc.
diff --git a/doc/ChangeLog b/doc/ChangeLog
index 0a7f20f..5c0143b 100644
--- a/doc/ChangeLog
+++ b/doc/ChangeLog
@@ -1,3 +1,8 @@
+2020-10-28 Arnold D. Robbins <arnold@skeeve.com>
+
+ * gawktexi.in (Other Arguments): Add a sidebar about quoting shell
+ variables on the command line. Based on a bug list discussion in 2018.
+
2020-10-22 Arnold D. Robbins <arnold@skeeve.com>
* texinfo.tex: Updated from GNULIB.
diff --git a/doc/gawk.info b/doc/gawk.info
index fd8f203..03c3a88 100644
--- a/doc/gawk.info
+++ b/doc/gawk.info
@@ -2980,6 +2980,29 @@ example:
the value of 'FS' is not strictly necessary. It remains for historical
compatibility.
+ Quoting Shell Variables On The 'awk' Command Line
+
+ Small 'awk' programs are often embedded in larger shell scripts, so
+it's worthwhile to understand some shell basics. Consider the
+following:
+
+ f=""
+ awk '{ print("hi") }' $f
+
+ In this case, 'awk' reads from standard input instead of trying to
+open any command line files. To the unwary, this looks like 'awk' is
+hanging.
+
+ However 'awk' doesn't see an explicit empty string. When a variable
+expansion is the null string, _and_ it's not quoted, the shell simply
+removes it from the command line. To demonstrate:
+
+ $ f=""
+ $ awk 'BEGIN { print ARGC }' $f
+ -| 1
+ $ awk 'BEGIN { print ARGC }' "$f"
+ -| 2
+
File: gawk.info, Node: Naming Standard Input, Next: Environment Variables,
Prev: Other Arguments, Up: Invoking Gawk
@@ -36793,6 +36816,8 @@ Index
* NR variable <1>: Auto-set. (line 143)
* NR variable, changing: Auto-set. (line 409)
* null strings, in gawk arguments, quoting and: Quoting. (line 82)
+* null strings, in gawk arguments, quoting and <1>: Other Arguments.
+ (line 73)
* null strings: awk split records. (line 121)
* null strings <1>: Regexp Field Splitting.
(line 43)
@@ -37170,6 +37195,7 @@ Index
* quoting, in gawk command lines: Long. (line 26)
* quoting, for small awk programs: Comments. (line 27)
* quoting, in gawk command lines, tricks for: Quoting. (line 91)
+* quoting, in gawk command lines <1>: Other Arguments. (line 73)
* r debugger command (alias for run): Debugger Execution Control.
(line 62)
* Rakitzis, Byron: History Sorting. (line 25)
@@ -37395,6 +37421,7 @@ Index
* shell function, gawklibpath_prepend: Shell Startup Files. (line 25)
* shell function, gawklibpath_append: Shell Startup Files. (line 29)
* shell quoting, rules for: Quoting. (line 6)
+* shell quoting, rules for <1>: Other Arguments. (line 73)
* shells, scripts: One-shot. (line 22)
* shells, quoting, rules for: Quoting. (line 18)
* shells, sea: Undocumented. (line 9)
@@ -37435,6 +37462,8 @@ Index
(line 24)
* sidebar, Recipe for a Programming Language: History. (line 6)
* sidebar, Understanding #!: Executable Scripts. (line 27)
+* sidebar, Quoting Shell Variables On The awk Command Line: Other Arguments.
+ (line 71)
* sidebar, Backslash Before Regular Characters: Escape Sequences.
(line 106)
* sidebar, Escape Sequences for Metacharacters: Escape Sequences.
@@ -37948,559 +37977,559 @@ Node: Options120292
Ref: Options-Footnote-1138206
Ref: Options-Footnote-2138437
Node: Other Arguments138462
-Node: Naming Standard Input141771
-Node: Environment Variables142981
-Node: AWKPATH Variable143539
-Ref: AWKPATH Variable-Footnote-1146951
-Ref: AWKPATH Variable-Footnote-2146985
-Node: AWKLIBPATH Variable147356
-Ref: AWKLIBPATH Variable-Footnote-1149053
-Node: Other Environment Variables149428
-Node: Exit Status153249
-Node: Include Files153926
-Node: Loading Shared Libraries157616
-Node: Obsolete159044
-Node: Undocumented159736
-Node: Invoking Summary160033
-Node: Regexp162874
-Node: Regexp Usage164328
-Node: Escape Sequences166365
-Node: Regexp Operators172606
-Node: Regexp Operator Details173091
-Ref: Regexp Operator Details-Footnote-1179523
-Node: Interval Expressions179670
-Ref: Interval Expressions-Footnote-1181091
-Node: Bracket Expressions181189
-Ref: table-char-classes183665
-Node: Leftmost Longest186991
-Node: Computed Regexps188294
-Node: GNU Regexp Operators191721
-Node: Case-sensitivity195458
-Ref: Case-sensitivity-Footnote-1198324
-Ref: Case-sensitivity-Footnote-2198559
-Node: Regexp Summary198667
-Node: Reading Files200133
-Node: Records202402
-Node: awk split records203477
-Node: gawk split records208752
-Ref: gawk split records-Footnote-1213485
-Node: Fields213522
-Node: Nonconstant Fields216263
-Ref: Nonconstant Fields-Footnote-1218499
-Node: Changing Fields218703
-Node: Field Separators224734
-Node: Default Field Splitting227432
-Node: Regexp Field Splitting228550
-Node: Single Character Fields231903
-Node: Command Line Field Separator232963
-Node: Full Line Fields236181
-Ref: Full Line Fields-Footnote-1237703
-Ref: Full Line Fields-Footnote-2237749
-Node: Field Splitting Summary237850
-Node: Constant Size239924
-Node: Fixed width data240656
-Node: Skipping intervening244123
-Node: Allowing trailing data244921
-Node: Fields with fixed data245958
-Node: Splitting By Content247476
-Ref: Splitting By Content-Footnote-1251259
-Node: More CSV251422
-Node: Testing field creation252732
-Node: Multiple Line254357
-Node: Getline260634
-Node: Plain Getline263103
-Node: Getline/Variable265676
-Node: Getline/File266827
-Node: Getline/Variable/File268215
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-Node: Special Files324951
-Node: Other Inherited Files325568
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-Node: Close Files And Pipes328378
-Ref: table-close-pipe-return-values335285
-Ref: Close Files And Pipes-Footnote-1336098
-Ref: Close Files And Pipes-Footnote-2336246
-Node: Nonfatal336398
-Node: Output Summary338736
-Node: Output Exercises339958
-Node: Expressions340637
-Node: Values341825
-Node: Constants342503
-Node: Scalar Constants343194
-Ref: Scalar Constants-Footnote-1345704
-Node: Nondecimal-numbers345954
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-Node: Using Constant Regexps349481
-Node: Standard Regexp Constants350103
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-Node: Uninitialized Subscripts521994
-Node: Delete523613
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-Ref: Numeric Functions-Footnote-2546760
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-Ref: String Functions-Footnote-2571349
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-Ref: I/O Functions-Footnote-2587557
-Node: Time Functions587677
-Ref: Time Functions-Footnote-1598348
-Ref: Time Functions-Footnote-2598416
-Ref: Time Functions-Footnote-3598574
-Ref: Time Functions-Footnote-4598685
-Ref: Time Functions-Footnote-5598797
-Ref: Time Functions-Footnote-6599024
-Node: Bitwise Functions599290
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-Ref: Bitwise Functions-Footnote-2606120
-Node: Type Functions606311
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-Ref: Definition Syntax-Footnote-1617331
-Node: Function Example617402
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-Node: Function Calling620346
-Node: Calling A Function620934
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-Node: Pass By Value/Reference624886
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-Node: Return Statement629697
-Node: Dynamic Typing632676
-Node: Indirect Calls633606
-Ref: Indirect Calls-Footnote-1643858
-Node: Functions Summary643986
-Node: Library Functions646691
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-Ref: Library Functions-Footnote-2650441
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-Ref: Library Names-Footnote-2654502
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-Node: Strtonum Function655691
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-Node: Round Function662039
-Node: Cliff Random Function663579
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-Node: Join Function668120
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-Node: Getlocaltime Function670090
-Node: Readfile Function673832
-Node: Shell Quoting675809
-Node: Data File Management677210
-Node: Filetrans Function677842
-Node: Rewind Function681938
-Node: File Checking683847
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-Node: Empty Files685382
-Node: Ignoring Assigns687361
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-Node: Using extensions780088
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-Node: PC Installation1236452
-Node: PC Binary Installation1237290
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-Node: Cygwin1242395
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-Node: GNU Free Documentation License1380699
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+Ref: AWKPATH Variable-Footnote-1147653
+Ref: AWKPATH Variable-Footnote-2147687
+Node: AWKLIBPATH Variable148058
+Ref: AWKLIBPATH Variable-Footnote-1149755
+Node: Other Environment Variables150130
+Node: Exit Status153951
+Node: Include Files154628
+Node: Loading Shared Libraries158318
+Node: Obsolete159746
+Node: Undocumented160438
+Node: Invoking Summary160735
+Node: Regexp163576
+Node: Regexp Usage165030
+Node: Escape Sequences167067
+Node: Regexp Operators173308
+Node: Regexp Operator Details173793
+Ref: Regexp Operator Details-Footnote-1180225
+Node: Interval Expressions180372
+Ref: Interval Expressions-Footnote-1181793
+Node: Bracket Expressions181891
+Ref: table-char-classes184367
+Node: Leftmost Longest187693
+Node: Computed Regexps188996
+Node: GNU Regexp Operators192423
+Node: Case-sensitivity196160
+Ref: Case-sensitivity-Footnote-1199026
+Ref: Case-sensitivity-Footnote-2199261
+Node: Regexp Summary199369
+Node: Reading Files200835
+Node: Records203104
+Node: awk split records204179
+Node: gawk split records209454
+Ref: gawk split records-Footnote-1214187
+Node: Fields214224
+Node: Nonconstant Fields216965
+Ref: Nonconstant Fields-Footnote-1219201
+Node: Changing Fields219405
+Node: Field Separators225436
+Node: Default Field Splitting228134
+Node: Regexp Field Splitting229252
+Node: Single Character Fields232605
+Node: Command Line Field Separator233665
+Node: Full Line Fields236883
+Ref: Full Line Fields-Footnote-1238405
+Ref: Full Line Fields-Footnote-2238451
+Node: Field Splitting Summary238552
+Node: Constant Size240626
+Node: Fixed width data241358
+Node: Skipping intervening244825
+Node: Allowing trailing data245623
+Node: Fields with fixed data246660
+Node: Splitting By Content248178
+Ref: Splitting By Content-Footnote-1251961
+Node: More CSV252124
+Node: Testing field creation253434
+Node: Multiple Line255059
+Node: Getline261336
+Node: Plain Getline263805
+Node: Getline/Variable266378
+Node: Getline/File267529
+Node: Getline/Variable/File268917
+Ref: Getline/Variable/File-Footnote-1270522
+Node: Getline/Pipe270610
+Node: Getline/Variable/Pipe273314
+Node: Getline/Coprocess274449
+Node: Getline/Variable/Coprocess275716
+Node: Getline Notes276458
+Node: Getline Summary279255
+Ref: table-getline-variants279679
+Node: Read Timeout280427
+Ref: Read Timeout-Footnote-1284333
+Node: Retrying Input284391
+Node: Command-line directories285590
+Node: Input Summary286496
+Node: Input Exercises289668
+Node: Printing290102
+Node: Print291936
+Node: Print Examples293393
+Node: Output Separators296173
+Node: OFMT298190
+Node: Printf299546
+Node: Basic Printf300331
+Node: Control Letters301905
+Node: Format Modifiers307069
+Node: Printf Examples313084
+Node: Redirection315570
+Node: Special FD322411
+Ref: Special FD-Footnote-1325579
+Node: Special Files325653
+Node: Other Inherited Files326270
+Node: Special Network327271
+Node: Special Caveats328131
+Node: Close Files And Pipes329080
+Ref: table-close-pipe-return-values335987
+Ref: Close Files And Pipes-Footnote-1336800
+Ref: Close Files And Pipes-Footnote-2336948
+Node: Nonfatal337100
+Node: Output Summary339438
+Node: Output Exercises340660
+Node: Expressions341339
+Node: Values342527
+Node: Constants343205
+Node: Scalar Constants343896
+Ref: Scalar Constants-Footnote-1346406
+Node: Nondecimal-numbers346656
+Node: Regexp Constants349657
+Node: Using Constant Regexps350183
+Node: Standard Regexp Constants350805
+Node: Strong Regexp Constants353993
+Node: Variables357005
+Node: Using Variables357662
+Node: Assignment Options359572
+Node: Conversion362043
+Node: Strings And Numbers362567
+Ref: Strings And Numbers-Footnote-1365630
+Node: Locale influences conversions365739
+Ref: table-locale-affects368497
+Node: All Operators369115
+Node: Arithmetic Ops369744
+Node: Concatenation372460
+Ref: Concatenation-Footnote-1375307
+Node: Assignment Ops375414
+Ref: table-assign-ops380405
+Node: Increment Ops381718
+Node: Truth Values and Conditions385178
+Node: Truth Values386252
+Node: Typing and Comparison387300
+Node: Variable Typing388120
+Ref: Variable Typing-Footnote-1394583
+Ref: Variable Typing-Footnote-2394655
+Node: Comparison Operators394732
+Ref: table-relational-ops395151
+Node: POSIX String Comparison398646
+Ref: POSIX String Comparison-Footnote-1400341
+Ref: POSIX String Comparison-Footnote-2400480
+Node: Boolean Ops400564
+Ref: Boolean Ops-Footnote-1405046
+Node: Conditional Exp405138
+Node: Function Calls406874
+Node: Precedence410751
+Node: Locales414410
+Node: Expressions Summary416042
+Node: Patterns and Actions418615
+Node: Pattern Overview419735
+Node: Regexp Patterns421412
+Node: Expression Patterns421954
+Node: Ranges425735
+Node: BEGIN/END428843
+Node: Using BEGIN/END429604
+Ref: Using BEGIN/END-Footnote-1432358
+Node: I/O And BEGIN/END432464
+Node: BEGINFILE/ENDFILE434777
+Node: Empty438008
+Node: Using Shell Variables438325
+Node: Action Overview440599
+Node: Statements442924
+Node: If Statement444772
+Node: While Statement446267
+Node: Do Statement448295
+Node: For Statement449443
+Node: Switch Statement452614
+Node: Break Statement455055
+Node: Continue Statement457147
+Node: Next Statement458974
+Node: Nextfile Statement461357
+Node: Exit Statement464009
+Node: Built-in Variables466412
+Node: User-modified467545
+Node: Auto-set475312
+Ref: Auto-set-Footnote-1492119
+Ref: Auto-set-Footnote-2492325
+Node: ARGC and ARGV492381
+Node: Pattern Action Summary496594
+Node: Arrays499024
+Node: Array Basics500353
+Node: Array Intro501197
+Ref: figure-array-elements503172
+Ref: Array Intro-Footnote-1505876
+Node: Reference to Elements506004
+Node: Assigning Elements508468
+Node: Array Example508959
+Node: Scanning an Array510718
+Node: Controlling Scanning513740
+Ref: Controlling Scanning-Footnote-1520196
+Node: Numeric Array Subscripts520512
+Node: Uninitialized Subscripts522696
+Node: Delete524315
+Ref: Delete-Footnote-1527067
+Node: Multidimensional527124
+Node: Multiscanning530219
+Node: Arrays of Arrays531810
+Node: Arrays Summary536578
+Node: Functions538671
+Node: Built-in539709
+Node: Calling Built-in540790
+Node: Numeric Functions542786
+Ref: Numeric Functions-Footnote-1546814
+Ref: Numeric Functions-Footnote-2547462
+Ref: Numeric Functions-Footnote-3547510
+Node: String Functions547782
+Ref: String Functions-Footnote-1571923
+Ref: String Functions-Footnote-2572051
+Ref: String Functions-Footnote-3572299
+Node: Gory Details572386
+Ref: table-sub-escapes574177
+Ref: table-sub-proposed575696
+Ref: table-posix-sub577059
+Ref: table-gensub-escapes578600
+Ref: Gory Details-Footnote-1579423
+Node: I/O Functions579577
+Ref: table-system-return-values586031
+Ref: I/O Functions-Footnote-1588111
+Ref: I/O Functions-Footnote-2588259
+Node: Time Functions588379
+Ref: Time Functions-Footnote-1599050
+Ref: Time Functions-Footnote-2599118
+Ref: Time Functions-Footnote-3599276
+Ref: Time Functions-Footnote-4599387
+Ref: Time Functions-Footnote-5599499
+Ref: Time Functions-Footnote-6599726
+Node: Bitwise Functions599992
+Ref: table-bitwise-ops600586
+Ref: Bitwise Functions-Footnote-1606649
+Ref: Bitwise Functions-Footnote-2606822
+Node: Type Functions607013
+Node: I18N Functions609876
+Node: User-defined611527
+Node: Definition Syntax612339
+Ref: Definition Syntax-Footnote-1618033
+Node: Function Example618104
+Ref: Function Example-Footnote-1621026
+Node: Function Calling621048
+Node: Calling A Function621636
+Node: Variable Scope622594
+Node: Pass By Value/Reference625588
+Node: Function Caveats628232
+Ref: Function Caveats-Footnote-1630279
+Node: Return Statement630399
+Node: Dynamic Typing633378
+Node: Indirect Calls634308
+Ref: Indirect Calls-Footnote-1644560
+Node: Functions Summary644688
+Node: Library Functions647393
+Ref: Library Functions-Footnote-1651000
+Ref: Library Functions-Footnote-2651143
+Node: Library Names651314
+Ref: Library Names-Footnote-1654981
+Ref: Library Names-Footnote-2655204
+Node: General Functions655290
+Node: Strtonum Function656393
+Node: Assert Function659415
+Node: Round Function662741
+Node: Cliff Random Function664281
+Node: Ordinal Functions665297
+Ref: Ordinal Functions-Footnote-1668360
+Ref: Ordinal Functions-Footnote-2668612
+Node: Join Function668822
+Ref: Join Function-Footnote-1670592
+Node: Getlocaltime Function670792
+Node: Readfile Function674534
+Node: Shell Quoting676511
+Node: Data File Management677912
+Node: Filetrans Function678544
+Node: Rewind Function682640
+Node: File Checking684549
+Ref: File Checking-Footnote-1685883
+Node: Empty Files686084
+Node: Ignoring Assigns688063
+Node: Getopt Function689613
+Ref: Getopt Function-Footnote-1704824
+Node: Passwd Functions705024
+Ref: Passwd Functions-Footnote-1713863
+Node: Group Functions713951
+Ref: Group Functions-Footnote-1721849
+Node: Walking Arrays722056
+Node: Library Functions Summary725064
+Node: Library Exercises726470
+Node: Sample Programs726935
+Node: Running Examples727705
+Node: Clones728433
+Node: Cut Program729657
+Node: Egrep Program739586
+Node: Id Program748597
+Node: Split Program758544
+Ref: Split Program-Footnote-1768318
+Node: Tee Program768491
+Node: Uniq Program771281
+Node: Wc Program778845
+Node: Bytes vs. Characters779242
+Node: Using extensions780790
+Node: wc program781548
+Node: Miscellaneous Programs786413
+Node: Dupword Program787626
+Node: Alarm Program789656
+Node: Translate Program794511
+Ref: Translate Program-Footnote-1799076
+Node: Labels Program799346
+Ref: Labels Program-Footnote-1802697
+Node: Word Sorting802781
+Node: History Sorting806853
+Node: Extract Program809078
+Node: Simple Sed817132
+Node: Igawk Program820206
+Ref: Igawk Program-Footnote-1834537
+Ref: Igawk Program-Footnote-2834739
+Ref: Igawk Program-Footnote-3834861
+Node: Anagram Program834976
+Node: Signature Program838038
+Node: Programs Summary839285
+Node: Programs Exercises840499
+Ref: Programs Exercises-Footnote-1844629
+Node: Advanced Features844715
+Node: Nondecimal Data846705
+Node: Array Sorting848296
+Node: Controlling Array Traversal848996
+Ref: Controlling Array Traversal-Footnote-1857364
+Node: Array Sorting Functions857482
+Ref: Array Sorting Functions-Footnote-1862573
+Node: Two-way I/O862769
+Ref: Two-way I/O-Footnote-1870490
+Ref: Two-way I/O-Footnote-2870677
+Node: TCP/IP Networking870759
+Node: Profiling873877
+Node: Advanced Features Summary883191
+Node: Internationalization885035
+Node: I18N and L10N886515
+Node: Explaining gettext887202
+Ref: Explaining gettext-Footnote-1893094
+Ref: Explaining gettext-Footnote-2893279
+Node: Programmer i18n893444
+Ref: Programmer i18n-Footnote-1898393
+Node: Translator i18n898442
+Node: String Extraction899236
+Ref: String Extraction-Footnote-1900368
+Node: Printf Ordering900454
+Ref: Printf Ordering-Footnote-1903240
+Node: I18N Portability903304
+Ref: I18N Portability-Footnote-1905760
+Node: I18N Example905823
+Ref: I18N Example-Footnote-1909098
+Ref: I18N Example-Footnote-2909171
+Node: Gawk I18N909280
+Node: I18N Summary909929
+Node: Debugger911270
+Node: Debugging912270
+Node: Debugging Concepts912711
+Node: Debugging Terms914520
+Node: Awk Debugging917095
+Ref: Awk Debugging-Footnote-1918040
+Node: Sample Debugging Session918172
+Node: Debugger Invocation918706
+Node: Finding The Bug920092
+Node: List of Debugger Commands926566
+Node: Breakpoint Control927899
+Node: Debugger Execution Control931593
+Node: Viewing And Changing Data934955
+Node: Execution Stack938496
+Node: Debugger Info940133
+Node: Miscellaneous Debugger Commands944204
+Node: Readline Support949266
+Node: Limitations950162
+Node: Debugging Summary952716
+Node: Namespaces953995
+Node: Global Namespace955106
+Node: Qualified Names956504
+Node: Default Namespace957503
+Node: Changing The Namespace958244
+Node: Naming Rules959858
+Node: Internal Name Management961706
+Node: Namespace Example962748
+Node: Namespace And Features965310
+Node: Namespace Summary966745
+Node: Arbitrary Precision Arithmetic968222
+Node: Computer Arithmetic969709
+Ref: table-numeric-ranges973475
+Ref: table-floating-point-ranges973968
+Ref: Computer Arithmetic-Footnote-1974626
+Node: Math Definitions974683
+Ref: table-ieee-formats977999
+Ref: Math Definitions-Footnote-1978602
+Node: MPFR features978707
+Node: FP Math Caution980425
+Ref: FP Math Caution-Footnote-1981497
+Node: Inexactness of computations981866
+Node: Inexact representation982826
+Node: Comparing FP Values984186
+Node: Errors accumulate985427
+Node: Getting Accuracy986860
+Node: Try To Round989570
+Node: Setting precision990469
+Ref: table-predefined-precision-strings991166
+Node: Setting the rounding mode992996
+Ref: table-gawk-rounding-modes993370
+Ref: Setting the rounding mode-Footnote-1997301
+Node: Arbitrary Precision Integers997480
+Ref: Arbitrary Precision Integers-Footnote-11000655
+Node: Checking for MPFR1000804
+Node: POSIX Floating Point Problems1002278
+Ref: POSIX Floating Point Problems-Footnote-11006563
+Node: Floating point summary1006601
+Node: Dynamic Extensions1008791
+Node: Extension Intro1010344
+Node: Plugin License1011610
+Node: Extension Mechanism Outline1012407
+Ref: figure-load-extension1012846
+Ref: figure-register-new-function1014411
+Ref: figure-call-new-function1015503
+Node: Extension API Description1017565
+Node: Extension API Functions Introduction1019278
+Ref: table-api-std-headers1021114
+Node: General Data Types1025363
+Ref: General Data Types-Footnote-11033993
+Node: Memory Allocation Functions1034292
+Ref: Memory Allocation Functions-Footnote-11038793
+Node: Constructor Functions1038892
+Node: API Ownership of MPFR and GMP Values1042358
+Node: Registration Functions1043671
+Node: Extension Functions1044371
+Node: Exit Callback Functions1049693
+Node: Extension Version String1050943
+Node: Input Parsers1051606
+Node: Output Wrappers1064327
+Node: Two-way processors1068839
+Node: Printing Messages1071104
+Ref: Printing Messages-Footnote-11072275
+Node: Updating ERRNO1072428
+Node: Requesting Values1073167
+Ref: table-value-types-returned1073904
+Node: Accessing Parameters1074840
+Node: Symbol Table Access1076077
+Node: Symbol table by name1076589
+Ref: Symbol table by name-Footnote-11079613
+Node: Symbol table by cookie1079741
+Ref: Symbol table by cookie-Footnote-11083926
+Node: Cached values1083990
+Ref: Cached values-Footnote-11087526
+Node: Array Manipulation1087679
+Ref: Array Manipulation-Footnote-11088770
+Node: Array Data Types1088807
+Ref: Array Data Types-Footnote-11091465
+Node: Array Functions1091557
+Node: Flattening Arrays1096055
+Node: Creating Arrays1103031
+Node: Redirection API1107798
+Node: Extension API Variables1110631
+Node: Extension Versioning1111342
+Ref: gawk-api-version1111771
+Node: Extension GMP/MPFR Versioning1113502
+Node: Extension API Informational Variables1115130
+Node: Extension API Boilerplate1116203
+Node: Changes from API V11120177
+Node: Finding Extensions1121749
+Node: Extension Example1122308
+Node: Internal File Description1123106
+Node: Internal File Ops1127186
+Ref: Internal File Ops-Footnote-11138536
+Node: Using Internal File Ops1138676
+Ref: Using Internal File Ops-Footnote-11141059
+Node: Extension Samples1141333
+Node: Extension Sample File Functions1142862
+Node: Extension Sample Fnmatch1150511
+Node: Extension Sample Fork1151998
+Node: Extension Sample Inplace1153216
+Node: Extension Sample Ord1156842
+Node: Extension Sample Readdir1157678
+Ref: table-readdir-file-types1158567
+Node: Extension Sample Revout1159634
+Node: Extension Sample Rev2way1160223
+Node: Extension Sample Read write array1160963
+Node: Extension Sample Readfile1162905
+Node: Extension Sample Time1164000
+Node: Extension Sample API Tests1165752
+Node: gawkextlib1166244
+Node: Extension summary1169162
+Node: Extension Exercises1172864
+Node: Language History1174106
+Node: V7/SVR3.11175762
+Node: SVR41177914
+Node: POSIX1179348
+Node: BTL1180729
+Node: POSIX/GNU1181458
+Node: Feature History1187236
+Node: Common Extensions1203555
+Node: Ranges and Locales1204838
+Ref: Ranges and Locales-Footnote-11209454
+Ref: Ranges and Locales-Footnote-21209481
+Ref: Ranges and Locales-Footnote-31209716
+Node: Contributors1209939
+Node: History summary1215936
+Node: Installation1217316
+Node: Gawk Distribution1218260
+Node: Getting1218744
+Node: Extracting1219707
+Node: Distribution contents1221345
+Node: Unix Installation1227825
+Node: Quick Installation1228507
+Node: Shell Startup Files1230921
+Node: Additional Configuration Options1232010
+Node: Configuration Philosophy1234325
+Node: Non-Unix Installation1236694
+Node: PC Installation1237154
+Node: PC Binary Installation1237992
+Node: PC Compiling1238427
+Node: PC Using1239544
+Node: Cygwin1243097
+Node: MSYS1244321
+Node: VMS Installation1244923
+Node: VMS Compilation1245714
+Ref: VMS Compilation-Footnote-11246943
+Node: VMS Dynamic Extensions1247001
+Node: VMS Installation Details1248686
+Node: VMS Running1250939
+Node: VMS GNV1255218
+Node: VMS Old Gawk1255953
+Node: Bugs1256424
+Node: Bug address1257087
+Node: Usenet1260069
+Node: Maintainers1261073
+Node: Other Versions1262258
+Node: Installation summary1269346
+Node: Notes1270555
+Node: Compatibility Mode1271349
+Node: Additions1272131
+Node: Accessing The Source1273056
+Node: Adding Code1274493
+Node: New Ports1280712
+Node: Derived Files1285087
+Ref: Derived Files-Footnote-11290747
+Ref: Derived Files-Footnote-21290782
+Ref: Derived Files-Footnote-31291380
+Node: Future Extensions1291494
+Node: Implementation Limitations1292152
+Node: Extension Design1293362
+Node: Old Extension Problems1294506
+Ref: Old Extension Problems-Footnote-11296024
+Node: Extension New Mechanism Goals1296081
+Ref: Extension New Mechanism Goals-Footnote-11299445
+Node: Extension Other Design Decisions1299634
+Node: Extension Future Growth1301747
+Node: Notes summary1302353
+Node: Basic Concepts1303511
+Node: Basic High Level1304192
+Ref: figure-general-flow1304474
+Ref: figure-process-flow1305159
+Ref: Basic High Level-Footnote-11308460
+Node: Basic Data Typing1308645
+Node: Glossary1311973
+Node: Copying1343858
+Node: GNU Free Documentation License1381401
+Node: Index1406521
End Tag Table
diff --git a/doc/gawk.texi b/doc/gawk.texi
index 0dc7a03..2a1e65c 100644
--- a/doc/gawk.texi
+++ b/doc/gawk.texi
@@ -4532,6 +4532,80 @@ Given the variable assignment feature, the @option{-F}
option for setting
the value of @code{FS} is not
strictly necessary. It remains for historical compatibility.
+@cindex sidebar @subentry Quoting Shell Variables On The @command{awk} Command
Line
+@ifdocbook
+@docbook
+<sidebar><title>Quoting Shell Variables On The @command{awk} Command
Line</title>
+@end docbook
+
+@cindex quoting @subentry in @command{gawk} command lines
+@cindex shell quoting, rules for
+@cindex null strings @subentry in @command{gawk} arguments, quoting and
+
+Small @command{awk} programs are often embedded in larger shell scripts,
+so it's worthwhile to understand some shell basics. Consider the following:
+
+@example
+f=""
+awk '@{ print("hi") @}' $f
+@end example
+
+In this case, @command{awk} reads from standard input instead of trying
+to open any command line files. To the unwary, this looks like @command{awk}
+is hanging.
+
+However @command{awk} doesn't see an explicit empty string. When a
+variable expansion is the null string, @emph{and} it's not quoted,
+the shell simply removes it from the command line. To demonstrate:
+
+@example
+$ @kbd{f=""}
+$ @kbd{awk 'BEGIN @{ print ARGC @}' $f}
+@print{} 1
+$ @kbd{awk 'BEGIN @{ print ARGC @}' "$f"}
+@print{} 2
+@end example
+
+@docbook
+</sidebar>
+@end docbook
+@end ifdocbook
+
+@ifnotdocbook
+@cartouche
+@center @b{Quoting Shell Variables On The @command{awk} Command Line}
+
+
+@cindex quoting @subentry in @command{gawk} command lines
+@cindex shell quoting, rules for
+@cindex null strings @subentry in @command{gawk} arguments, quoting and
+
+Small @command{awk} programs are often embedded in larger shell scripts,
+so it's worthwhile to understand some shell basics. Consider the following:
+
+@example
+f=""
+awk '@{ print("hi") @}' $f
+@end example
+
+In this case, @command{awk} reads from standard input instead of trying
+to open any command line files. To the unwary, this looks like @command{awk}
+is hanging.
+
+However @command{awk} doesn't see an explicit empty string. When a
+variable expansion is the null string, @emph{and} it's not quoted,
+the shell simply removes it from the command line. To demonstrate:
+
+@example
+$ @kbd{f=""}
+$ @kbd{awk 'BEGIN @{ print ARGC @}' $f}
+@print{} 1
+$ @kbd{awk 'BEGIN @{ print ARGC @}' "$f"}
+@print{} 2
+@end example
+@end cartouche
+@end ifnotdocbook
+
@node Naming Standard Input
@section Naming Standard Input
diff --git a/doc/gawktexi.in b/doc/gawktexi.in
index b584181..e733c4e 100644
--- a/doc/gawktexi.in
+++ b/doc/gawktexi.in
@@ -4442,6 +4442,36 @@ Given the variable assignment feature, the @option{-F}
option for setting
the value of @code{FS} is not
strictly necessary. It remains for historical compatibility.
+@sidebar Quoting Shell Variables On The @command{awk} Command Line
+@cindex quoting @subentry in @command{gawk} command lines
+@cindex shell quoting, rules for
+@cindex null strings @subentry in @command{gawk} arguments, quoting and
+
+Small @command{awk} programs are often embedded in larger shell scripts,
+so it's worthwhile to understand some shell basics. Consider the following:
+
+@example
+f=""
+awk '@{ print("hi") @}' $f
+@end example
+
+In this case, @command{awk} reads from standard input instead of trying
+to open any command line files. To the unwary, this looks like @command{awk}
+is hanging.
+
+However @command{awk} doesn't see an explicit empty string. When a
+variable expansion is the null string, @emph{and} it's not quoted,
+the shell simply removes it from the command line. To demonstrate:
+
+@example
+$ @kbd{f=""}
+$ @kbd{awk 'BEGIN @{ print ARGC @}' $f}
+@print{} 1
+$ @kbd{awk 'BEGIN @{ print ARGC @}' "$f"}
+@print{} 2
+@end example
+@end sidebar
+
@node Naming Standard Input
@section Naming Standard Input
-----------------------------------------------------------------------
Summary of changes:
doc/ChangeLog | 5 +
doc/gawk.info | 1135 ++++++++++++++++++++++++++++---------------------------
doc/gawk.texi | 74 ++++
doc/gawktexi.in | 30 ++
4 files changed, 691 insertions(+), 553 deletions(-)
hooks/post-receive
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