Thursday, 21 March 2013

AWK Cheat Sheet



 ===================== Predefined Variable Summary =====================

.-------------+-----------------------------------.---------------------.
| | | Support: |
| Variable | Description '-----.-------.-------'
| | | AWK | NAWK | GAWK |
'-------------+-----------------------------------+-----+-------+-------'
| FS | Input Field Separator, a space by | + | + | + |
| | default. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| OFS | Output Field Separator, a space | + | + | + |
| | by default. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| NF | The Number of Fields in the | + | + | + |
| | current input record. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| NR | The total Number of input Records | + | + | + |
| | seen so far. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| RS | Record Separator, a newline by | + | + | + |
| | default. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| ORS | Output Record Separator, a | + | + | + |
| | newline by default. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| FILENAME | The name of the current input | | | |
| | file. If no files are specified | | | |
| | on the command line, the value of | | | |
| | FILENAME is "-". However, | + | + | + |
| | FILENAME is undefined inside the | | | |
| | BEGIN block (unless set by | | | |
| | getline). | | | |
'-------------+-----------------------------------+-----+-------+-------'
| ARGC | The number of command line | | | |
| | arguments (does not include | | | |
| | options to gawk, or the program | - | + | + |
| | source). Dynamically changing the | | | |
| | contents of ARGV control the | - | + | + |
| | files used for data. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| ARGV | Array of command line arguments. | | | |
| | The array is indexed from 0 to | - | + | + |
| | ARGC - 1. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| ARGIND | The index in ARGV of the current | - | - | + |
| | file being processed. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| BINMODE | On non-POSIX systems, specifies | | | |
| | use of "binary" mode for all file | | | |
| | I/O.Numeric values of 1, 2, or 3, | | | |
| | specify that input files, output | | | |
| | files, or all files, respectively,| | | |
| | should use binary I/O. String | | | |
| | values of "r", or "w" specify | - | - | + |
| | that input files, or output files,| | | |
| | respectively, should use binary | | | |
| | I/O. String values of "rw" or | | | |
| | "wr" specify that all files | | | |
| | should use binary I/O. Any other | | | |
| | string value is treated as "rw", | | | |
| | but generates a warning message. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| CONVFMT | The CONVFMT variable is used to | | | |
| | specify the format when | - | - | + |
| | converting a number to a string. | | | |
| | Default: "%.6g" | | | |
'-------------+-----------------------------------+-----+-------+-------'
| ENVIRON | An array containing the values | - | - | + |
| | of the current environment. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| ERRNO | If a system error occurs either | | | |
| | doing a redirection for getline, | | | |
| | during a read for getline, or | | | |
| | during a close(), then ERRNO will | - | - | + |
| | contain a string describing the | | | |
| | error. The value is subject to | | | |
| | translation in non-English locales. | | |
'-------------+-----------------------------------+-----+-------+-------'
| FIELDWIDTHS | A white-space separated list of | | | |
| | fieldwidths. When set, gawk | | | |
| | parses the input into fields of | - | - | + |
| | fixed width, instead of using the | | | |
| | value of the FS variable as the | | | |
| | field separator. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| FNR | Contains number of lines read, | - | + | + |
| | but is reset for each file read. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| IGNORECASE | Controls the case-sensitivity of | | | |
| | all regular expression and string | | | |
| | operations. If IGNORECASE has a | | | |
| | non-zero value, then string | | | |
| | comparisons and pattern matching | | | |
| | in rules, field splitting | | | |
| | with FS, record separating | | | |
| | with RS, regular expression | | | |
| | matching with ~ and !~, and the | - | - | + |
| | gensub(), gsub(), index(), | | | |
| | match(), split(), and sub() | | | |
| | built-in functions all ignore | | | |
| | case when doing regular | | | |
| | expression operations. | | | |
| | NOTE: Array subscripting is not | | | |
| | affected. However, the asort() | | | |
| | and asorti() functions are | | | |
| | affected | | | |
'-------------+-----------------------------------+-----+-------+-------'
| LINT | Provides dynamic control of the | | | |
| | --lint option from within an AWK | - | - | + |
| | program. When true, gawk prints | | | |
| | lint warnings. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| OFMT | The default output format for | - | + | + |
| | numbers. Default: "%.6g" | | | |
'-------------+-----------------------------------+-----+-------+-------'
| PROCINFO | The elements of this array | | | |
| | provide access to information | | | |
| | about the running AWK program. | | | |
| | PROCINFO["egid"]: | | | |
| | the value of the getegid(2) | | | |
| | system call. | | | |
| | PROCINFO["euid"]: | | | |
| | the value of the geteuid(2) | | | |
| | system call. | | | |
| | PROCINFO["FS"]: | | | |
| | "FS" if field splitting with FS | | | |
| | is in effect, or "FIELDWIDTHS" | | | |
| | if field splitting with | | | |
| | FIELDWIDTHS is in effect. | | | |
| | PROCINFO["gid"]: | - | - | + |
| | the value of the getgid(2) system | | | |
| | call. | | | |
| | PROCINFO["pgrpid"]: | | | |
| | the process group ID of the | | | |
| | current process. | | | |
| | PROCINFO["pid"]: | | | |
| | the process ID of the current | | | |
| | process. | | | |
| | PROCINFO["ppid"]: | | | |
| | the parent process ID of the | | | |
| | current process. | | | |
| | PROCINFO["uid"] | | | |
| | the value of the getuid(2) system | | | |
| | call. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| RT | The record terminator. Gawk sets | | | |
| | RT to the input text that matched | - | - | + |
| | the character or regular | | | |
| | expression specified by RS. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| RSTART | The index of the first character | - | + | + |
| | matched by match(); 0 if no match.| | | |
'-------------+-----------------------------------+-----+-------+-------'
| RLENGTH | The length of the string matched | - | + | + |
| | by match(); -1 if no match. | | | |
'-------------+-----------------------------------+-----+-------+-------'
| SUBSEP | The character used to separate | | | |
| | multiple subscripts in array | | | |
| | elements.Default: "\034" | - | + | + |
| | (non-printable character, | | | |
| | dec: 28, hex: 1C) | | | |
'-------------+-----------------------------------+-----+-------+-------'
| TEXTDOMAIN | The text domain of the AWK | | | |
| | program; used to find the | - | - | + |
| | localized translations for the | | | |
| | program's strings. | | | |
'-------------'-----------------------------------'-----'-------'-------'


============================ I/O Statements ===========================

.---------------------.-------------------------------------------------.
| | |
| Statement | Description |
| | |
'---------------------+-------------------------------------------------'
| close(file [, how]) | Close file, pipe or co-process. The optional |
| | how should only be used when closing one end of |
| | a two-way pipe to a co-process. It must be a |
| | string value, either "to" or "from". |
'---------------------+-------------------------------------------------'
| getline | Set $0 from next input record; set NF, NR, FNR. |
| | Returns 0 on EOF and �1 on an error. Upon an |
| | error, ERRNO contains a string describing the |
| | problem. |
'---------------------+-------------------------------------------------'
| getline <file | Set $0 from next record of file; set NF. |
'---------------------+-------------------------------------------------'
| getline var | Set var from next input record; set NR, FNR. |
'---------------------+-------------------------------------------------'
| getline var <file | Set var from next record of file. |
'---------------------+-------------------------------------------------'
| command | | Run command piping the output either into $0 or |
| getline [var] | var, as above. If using a pipe or co-process |
| | to getline, or from print or printf within a |
| | loop, you must use close() to create new |
| | instances |
'---------------------+-------------------------------------------------'
| command |& | Run command as a co-process piping the output |
| getline [var] | either into $0 or var, as above. Co-processes |
| | are a gawk extension. |
'---------------------+-------------------------------------------------'
| next | Stop processing the current input record. |
| | The next input record is read and processing |
| | starts over with the first pattern in the AWK |
| | program. If the end of the input data is |
| | reached, the END block(s), if any, are executed.|
'---------------------+-------------------------------------------------'
| nextfile | Stop processing the current input file. The |
| | next input record read comes from the next |
| | input file. FILENAME and ARGIND are updated, |
| | FNR is reset to 1, and processing starts over |
| | with the first pattern in the AWK program. If |
| | the end of the input data is reached, the END |
| | block(s), are executed. |
'---------------------+-------------------------------------------------'
| print | Prints the current record. The output record is |
| | terminated with the value of the ORS variable. |
'---------------------+-------------------------------------------------'
| print expr-list | Prints expressions. Each expression is |
| | separated by the value of the OFS variable. |
| | The output record is terminated with the value |
| | of the ORS variable. |
'---------------------+-------------------------------------------------'
| print expr-list | Prints expressions on file. Each expression is |
| >file | separated by the value of the OFS variable. The |
| | output record is terminated with the value of |
| | the ORS variable. |
'---------------------+-------------------------------------------------'
| printf fmt, | Format and print. |
| expr-list | |
'---------------------+-------------------------------------------------'
| printf fmt, | Format and print on file. |
| expr-list >file | |
'---------------------+-------------------------------------------------'
| system(cmd-line) | Execute the command cmd-line, and return the |
| | exit status. |
'---------------------+-------------------------------------------------'
| fflush([file]) | Flush any buffers associated with the open |
| | output file or pipe file. If file is missing, |
| | then stdout is flushed. If file is the null |
| | string, then all open output files and pipes |
| | have their buffers flushed. |
'---------------------+-------------------------------------------------'
| print ... >> file | Appends output to the file. |
'---------------------+-------------------------------------------------'
| print ... | command | Writes on a pipe. |
'---------------------+-------------------------------------------------'
| print ... |& | Sends data to a co-process. |
| command | |
'---------------------'-------------------------------------------------'


=========================== Numeric Functions =========================

.---------------------.-------------------------------------------------.
| | |
| Function | Description |
| | |
'---------------------+-------------------------------------------------'
| atan2(y, x) | Returns the arctangent of y/x in radians. |
'---------------------+-------------------------------------------------'
| cos(expr) | Returns the cosine of expr, which is in radians.|
'---------------------+-------------------------------------------------'
| exp(expr) | The exponential function. |
'---------------------+-------------------------------------------------'
| int(expr) | Truncates to integer. |
'---------------------+-------------------------------------------------'
| log(expr) | The natural logarithm function. |
'---------------------+-------------------------------------------------'
| rand() | Returns a random number N, between 0 and 1, |
| | such that 0 <= N < 1. |
'---------------------+-------------------------------------------------'
| sin(expr) | Returns the sine of expr, which is in radians. |
'---------------------+-------------------------------------------------'
| sqrt(expr) | The square root function. |
'---------------------+-------------------------------------------------'
| srand([expr]) | Uses expr as a new seed for the random number |
| | generator. If no expr is provided, the time of |
| | day is used. The return value is the previous |
| | seed for the random number generator. |
'---------------------'-------------------------------------------------'


====================== Bit Manipulation Functions =====================

.---------------------.-------------------------------------------------.
| | |
| Function | Description |
| | |
'---------------------+-------------------------------------------------'
| and(v1, v2) | Return the bitwise AND of the values provided |
| | by v1 and v2. |
'---------------------+-------------------------------------------------'
| compl(val) | Return the bitwise complement of val. |
'---------------------+-------------------------------------------------'
| lshift(val, count) | Return the value of val, shifted left by |
| | count bits. |
'---------------------+-------------------------------------------------'
| or(v1, v2) | Return the bitwise OR of the values provided by |
| | v1 and v2. |
'---------------------+-------------------------------------------------'
| rshift(val, count) | Return the value of val, shifted right by |
| | count bits. |
'---------------------+-------------------------------------------------'
| xor(v1, v2) | Return the bitwise XOR of the values provided |
| | by v1 and v2. |
'---------------------'-------------------------------------------------'


=========================== String Functions ==========================

.---------------------.-------------------------------------------------.
| | |
| Function | Description |
| | |
'---------------------+-------------------------------------------------'
| asort(s [, d]) | Returns the number of elements in the source |
| | array s. The contents of s are sorted using |
| | gawk's normal rules for comparing values, and |
| | the indexes of the sorted values of s are |
| | replaced with sequential integers starting with |
| | 1. If the optional destination array d is |
| | specified, then s is first duplicated into d, |
| | and then d is sorted, leaving the indexes of |
| | the source array s unchanged. |
'---------------------+-------------------------------------------------'
| asorti(s [, d]) | Returns the number of elements in the source |
| | array s. The behavior is the same as that of |
| | asort(), except that the array indices are |
| | used for sorting, not the array values. When |
| | done, the array is indexed numerically, and the |
| | values are those of the original indices. The |
| | original values are lost; thus provide a second |
| | array if you wish to preserve the original. |
'---------------------+-------------------------------------------------'
| gensub(r, s, | Search the target string t for matches of the |
| h [, t]) | regular expression r. If h is a string |
| | beginning with g or G, then replace all matches |
| | of r with s. Otherwise, h is a number |
| | indicating which match of r to replace. If t is |
| | not supplied, $0 is used instead. Within the |
| | replacement text s, the sequence \n, where n is |
| | a digit from 1 to 9, may be used to indicate |
| | just the text that matched the n'th |
| | parenthesized subexpression. The sequence \0 |
| | represents the entire matched text, as does the |
| | character &. Unlike sub() and gsub(), the |
| | modified string is returned as the result of |
| | the function, and the original target string |
| | is not changed. |
'---------------------+-------------------------------------------------'
| gsub(r, s [, t]) | For each substring matching the regular |
| | expression r in the string t, substitute the |
| | string s, and return the number of |
| | substitutions. If t is not supplied, use $0. |
| | An & in the replacement text is replaced with |
| | the text that was actually matched. Use \& to |
| | get a literal &. (This must be |
| | typed as "\\&") |
'---------------------+-------------------------------------------------'
| index(s, t) | Returns the index of the string t in the |
| | string s, or 0 if t is not present. (This |
| | implies that characterindices start at one.) |
'---------------------+-------------------------------------------------'
| length([s]) | Returns the length of the string s, or the |
| | length of $0 if s is not supplied. |
'---------------------+-------------------------------------------------'
| match(s, r [, a]) | Returns the position in s where the regular |
| | expression r occurs, or 0 if r is not present, |
| | and sets the values of RSTART and RLENGTH. |
| | Note that the argument order is the same as for |
| | the ~ operator: str ~ re. If array a is |
| | provided, a is cleared and then elements 1 |
| | through n are filled with the portions of s |
| | that match the corresponding parenthesized |
| | subexpression in r. The 0'th element of a |
| | contains the portion of s matched by the entire |
| | regular expression r. Subscripts a[n, "start"], |
| | and a[n, "length"] provide the starting index |
| | in the string and length respectively, of each |
| | matching substring. |
'---------------------+-------------------------------------------------'
| split(s, a [, r]) | Splits the string s into the array a on the |
| | regular expression r, and returns the number of |
| | fields. If r is omitted, FS is used instead. |
| | The array a is cleared first. Splitting behaves |
| | identically to field splitting. |
'---------------------+-------------------------------------------------'
| sprintf(fmt, | Prints expr-list according to fmt, and returns |
| expr-list) | the resulting string. |
'---------------------+-------------------------------------------------'
| strtonum(str) | Examines str, and returns its numeric value. |
| | If str begins with a leading 0, strtonum() |
| | assumes that str is an octal number. If str |
| | begins with a leading 0x or 0X, strtonum() |
| | assumes that str is a hexadecimal number. |
'---------------------+-------------------------------------------------'
| sub(r, s [, t]) | Just like gsub(), but only the first matching |
| | substring is replaced. |
'---------------------+-------------------------------------------------'
| substr(s, i [, n]) | Returns the at most n-character substring of s |
| | starting at i. If n is omitted, the rest of s |
| | is used. |
'---------------------+-------------------------------------------------'
| tolower(str) | Returns a copy of the string str, with all the |
| | upper-case characters in str translated to |
| | their corresponding lower-case counterparts. |
| | Non-alphabetic characters are left unchanged. |
'---------------------+-------------------------------------------------'
| toupper(str) | Returns a copy of the string str, with all the |
| | lower-case characters in str translated to |
| | their corresponding upper-case counterparts. |
| | Non-alphabetic characters are left unchanged. |
'---------------------'-------------------------------------------------'


============================ Time Functions ===========================

.---------------------.-------------------------------------------------.
| | |
| Function | Description |
| | |
'---------------------+-------------------------------------------------'
| mktime(datespec) | Turns datespec into a time stamp of the same |
| | form as returned by systime(). The datespec is |
| | a string of the form YYYY MM DD HH MM SS[ DST]. |
| | The contents of the string are six or seven |
| | numbers representing respectively the full year |
| | including century, the month from 1 to 12, the |
| | day of the month from 1 to 31, the hour of the |
| | day from 0 to 23, the minute from 0 to 59, and |
| | the second from 0 to 60, and an optional |
| | daylight saving flag. The values of these |
| | numbers need not be within the ranges |
| | specified; for example, an hour of -1 means 1 |
| | hour before midnight. The origin-zero Gregorian |
| | calendar is assumed, with year 0 preceding year |
| | 1 and year -1 preceding year 0. The time is |
| | assumed to be in the local timezone. If the |
| | daylight saving flag is positive, the time is |
| | assumed to be daylight saving time; if zero, |
| | the time is assumed to be standard time; and if |
| | negative (the default), mktime() attempts to |
| | determine whether daylight saving time is in |
| | effect for the specified time. If datespec does |
| | not contain enough elements or if the resulting |
| | time is out of range, mktime() returns -1. |
'---------------------+-------------------------------------------------'
| strftime([format | Formats timestamp according to the |
| [, timestamp]]) | specification in format. The timestamp should |
| | be of the same form as returned by systime(). |
| | If timestamp is missing, the current time of |
| | day is used.If format is missing, a default |
| | format equivalent to the output of date(1) is |
| | used. See the specification for the strftime() |
| | function in ANSI C for the format conversions |
| | that are guaranteed to be available. A |
| | public-domain version of strftime(3) and a man |
| | page for it come with gawk; if that version was |
| | used to build gawk, then all of the conversions |
| | described in that man page are available to |
| | gawk. |
'---------------------+-------------------------------------------------'
| systime() | Returns the current time of day as the number |
| | of seconds since the Epoch (1970-01-01 00:00:00 |
| | UTC on POSIX systems). |
'---------------------'-------------------------------------------------'


=============== Internationalization (I18N) Functions ================

.---------------------.-------------------------------------------------.
| | |
| Function | |
| | |
| Description | |
| | |
'---------------------+-------------------------------------------------'
| bindtextdomain(directory [, domain]) |
| |
| Specifies the directory where gawk looks for the .mo files. It |
| returns the directory where domain is ``bound.'' The default domain |
| is the value of TEXTDOMAIN. If directory is the null string (""), |
| then bindtextdomain() returns the current binding for the given domain|
'---------------------+-------------------------------------------------'
| dcgettext(string [, domain [, category]]) |
| |
| Returns the translation of string in text domain domain for locale |
| category category. The default value for domain is the current value |
| of TEXTDOMAIN. The default value for category is "LC_MESSAGES". If |
| you supply a value for category, it must be a string equal to one of |
| the known locale categories. You must also supply a text domain. Use |
| TEXTDOMAIN if you want to use the current domain. |
'---------------------+-------------------------------------------------'
| dcngettext(string1 , string2 , number [, domain [, category]]) |
| |
| Returns the plural form used for number of the translation of string1 |
| and string2 in text domain domain for locale category category. The |
| default value for domain is the current value of TEXTDOMAIN. The |
| default value for category is "LC_MESSAGES". If you supply a value |
| for category, it must be a string equal to one of the known locale |
| categories. You must also supply a text domain. Use TEXTDOMAIN if |
| you want to use the current domain. |
'---------------------'-------------------------------------------------'




=============== GNU AWK's Command Line Argument Summary ===============

.-------------------------.---------------------------------------------.
| | |
| Argument | Description |
| | |
'-------------------------+---------------------------------------------'
| -F fs | Use fs for the input field separator |
| --field-sepearator fs | (the value of the FS predefined variable). |
'-------------------------+---------------------------------------------'
| -v var=val | Assign the value val to the variable var, |
| --assign var=val | before execution of the program begins. |
| | Such variable values are available to the |
| | BEGIN block of an AWK program. |
'-------------------------+---------------------------------------------'
| -f program-file | Read the AWK program source from the file |
| --file program-file | program-file, instead of from the first |
| | command line argument. Multiple -f |
| | (or --file) options may be used. |
'-------------------------+---------------------------------------------'
| -mf NNN | Set various memory limits to the value NNN. |
| -mr NNN | The f flag sets the maximum number of |
| | fields, and the r flag sets the maximum |
| | record size. (Ignored by gawk, since gawk |
| | has no pre-defined limits) |
'-------------------------+---------------------------------------------'
| -W compat | Run in compatibility mode. In compatibility |
| -W traditional | mode, gawk behaves identically to UNIX awk; |
| --compat--traditional | none of the GNU-specific extensions are |
| | recognized. |
'-------------------------+---------------------------------------------'
| -W copyleft | Print the short version of the GNU copyright|
| -W copyright | information message on the standard output |
| --copyleft | and exit successfully. |
| --copyright | |
'-------------------------+---------------------------------------------'
| -W dump-variables[=file]| Print a sorted list of global variables, |
| --dump-variables[=file] | their types and final values to file. If no |
| | file is provided, gawk uses a file named |
| | awkvars.out in the current directory. |
'-------------------------+---------------------------------------------'
| -W help | Print a relatively short summary of the |
| -W usage | available options on the standard output. |
| --help | |
| --usage | |
'-------------------------+---------------------------------------------'
|-W lint[=value] | Provide warnings about constructs that |
|--lint[=value] | are dubious or non-portable to other AWK |
| | impl�s. With argument fatal, lint warnings |
| | become fatal errors. With an optional |
| | argument of invalid, only warnings about |
| | things that are actually invalid are |
| | issued. (This is not fully implemented yet.)|
'-------------------------+---------------------------------------------'
| -W lint-old--lint-old | Provide warnings about constructs that are |
| | not portable to the original version of |
| | Unix awk. |
'-------------------------+---------------------------------------------'
| -W gen-po--gen-po | Scan and parse the AWK program, and |
| | generate a GNU .po format file on standard |
| | output with entries for all localizable |
| | strings in the program. The program itself |
| | is not executed. |
'-------------------------+---------------------------------------------'
| -W non-decimal-data | Recognize octal and hexadecimal values in |
| --non-decimal-data | input data. |
'-------------------------+---------------------------------------------'
| -W posix--posix | This turns on compatibility mode, with the |
| | following additional restrictions: |
| | o \x escape sequences are not recognized. |
| | o Only space and tab act as field |
| | separators when FS is set to a single |
| | space, new-line does not. |
| | o You cannot continue lines after ? and :. |
| | o The synonym func for the keyword function|
| | is not recognized. |
| | o The operators ** and **= cannot be used |
| | in place of ^ and ^=.� The fflush() |
| | function is not available. |
'-------------------------+---------------------------------------------'
| -W profile[=prof_file] | Send profiling data to prof_file. |
| --profile[=prof_file] | The default is awkprof.out. When run with |
| | gawk, the profile is just a "pretty |
| | printed" version of the program. When run |
| | with pgawk, the profile contains execution |
| | counts of each statement in the program |
| | in the left margin and function call counts |
| | for each user-defined function. |
'-------------------------+---------------------------------------------'
| -W re-interval | Enable the use of interval expressions in |
| --re-interval | regular expression matching. Interval |
| | expressions were not traditionally |
| | available in the AWK language. |
'-------------------------+---------------------------------------------'
| -W source program-text | Use program-text as AWK program source |
| --source program-text | code. This option allows the easy |
| | intermixing of library functions (used via |
| | the -f and --file options) with source code |
| | entered on the command line. |
'-------------------------+---------------------------------------------'
| -W version | Print version information for this |
| --version | particular copy of gawk on the standard |
| | output. |
'-------------------------+---------------------------------------------'
| -- | Signal the end of options. This is useful |
| | to allow further arguments to the AWK |
| | program itself to start with a "-". This |
| | is mainly for consistency with the argument |
| | parsing convention used by most other POSIX |
| | programs. |
'-------------------------'---------------------------------------------'

=======================================================================

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