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diff --git a/usr.bin/sed/USD.doc/Makefile b/usr.bin/sed/USD.doc/Makefile new file mode 100644 index 00000000000..68eb1fdfc6d --- /dev/null +++ b/usr.bin/sed/USD.doc/Makefile @@ -0,0 +1,7 @@ +# $OpenBSD: Makefile,v 1.1 2003/06/26 16:22:04 mickey Exp $ + +DIR= usd/15.sed +SRCS= sed +MACROS= -ms + +.include <bsd.doc.mk> diff --git a/usr.bin/sed/USD.doc/sed b/usr.bin/sed/USD.doc/sed new file mode 100644 index 00000000000..6558f9edaac --- /dev/null +++ b/usr.bin/sed/USD.doc/sed @@ -0,0 +1,1298 @@ +.\" $OpenBSD: sed,v 1.1 2003/06/26 16:22:04 mickey Exp $ +.\" +.\" Copyright (C) Caldera International Inc. 2001-2002. +.\" All rights reserved. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code and documentation must retain the above +.\" copyright notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed or owned by Caldera +.\" International, Inc. +.\" 4. Neither the name of Caldera International, Inc. nor the names of other +.\" contributors may be used to endorse or promote products derived from +.\" this software without specific prior written permission. +.\" +.\" USE OF THE SOFTWARE PROVIDED FOR UNDER THIS LICENSE BY CALDERA +.\" INTERNATIONAL, INC. AND CONTRIBUTORS ``AS IS'' AND ANY EXPRESS OR +.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES +.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. +.\" IN NO EVENT SHALL CALDERA INTERNATIONAL, INC. BE LIABLE FOR ANY DIRECT, +.\" INDIRECT INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES +.\" (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR +.\" SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, +.\" STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING +.\" IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE +.\" POSSIBILITY OF SUCH DAMAGE. +.\" +.\" @(#)sed 8.2 (Berkeley) 6/1/94 +.\" +.EH 'USD:15-%''SED \(em A Non-interactive Text Editor' +.OH 'SED \(em A Non-interactive Text Editor''USD:15-%' +.hw de-limit +.hw de-limit-ing +.\".RP +....TM 78-1270-1 39199 39199-11 +.ND August 15, 1978 +.TL +SED \(em A Non-interactive Text Editor +.AU "MH 2C-555" 3302 +Lee E. McMahon +.AI +.MH +.OK +\"Context search +\"Editing +.AB +.ul +Sed +is a non-interactive context editor +that runs on the +.UX +operating system. +.ul +Sed +is +designed to be especially useful in +three cases: +.in +1i +.LP +.ti -.5i +1) +To edit files too large for comfortable +interactive editing; +.ti -.5i +2) +To edit any size file when the sequence +of editing commands is too complicated to be comfortably +typed in interactive mode. +.ti -.5i +3) +To perform multiple `global' editing functions +efficiently in one pass through the input. +.in -1i +.LP +This memorandum constitutes a manual for users of +.ul +sed. +.AE +.CS 10 0 10 0 0 1 +.SH +Introduction +.LP +.ul +Sed +is a non-interactive context editor designed to be especially useful in +three cases: +.in +1i +.LP +.ti -.5i +1) +To edit files too large for comfortable +interactive editing; +.ti -.5i +2) +To edit any size file when the sequence +of editing commands is too complicated to be comfortably +typed in interactive mode; +.ti -.5i +3) +To perform multiple `global' editing functions +efficiently in one pass through the input. +.in -1i +.LP +Since only a few lines of the input reside in core +at one time, and no temporary files are used, +the effective size of file that can be edited is limited only +by the requirement that the input and output fit simultaneously +into available secondary storage. +.LP +Complicated editing scripts can be created separately and given +to +.ul +sed +as a command file. +For complex edits, this saves considerable typing, and its +attendant errors. +.ul +Sed +running from a command file is much more efficient than any interactive +editor known to the author, even if that editor +can be driven by a pre-written script. +.LP +The principal loss of functions compared to an interactive editor +are lack of relative addressing (because of the line-at-a-time +operation), and lack of immediate verification that a command has +done what was intended. +.LP +.ul +Sed +is a lineal descendant of the UNIX editor, +.ul +ed. +Because of the differences between interactive and non-interactive +operation, considerable changes have been made between +.ul +ed +and +.ul +sed; +even confirmed users of +.ul +ed +will frequently be surprised (and probably chagrined), +if they rashly use +.ul +sed +without reading Sections 2 and 3 of this document. +The most striking family resemblance between the two +editors is in the class of patterns (`regular expressions') they +recognize; +the code for matching patterns is copied almost +verbatim from the code for +.ul +ed, +and the description of regular expressions in Section 2 +is copied almost verbatim from the UNIX Programmer's +Manual[1]. (Both code and description were written by Dennis +M. Ritchie.) +.LP +.SH +1. Overall Operation +.LP +.ul +Sed +by default copies the standard input to the standard output, +perhaps performing one or more editing commands on each +line before writing it to the output. +This behavior may be modified by flags on the command line; +see Section 1.1 below. +.LP +The general format of an editing command is: +.LP +.in +1i +[address1,address2][function][arguments] +.LP +.in -1i +One or both addresses may be omitted; the format of addresses is +given in Section 2. +Any number of blanks or tabs may separate the addresses +from the function. +The function must be present; the available commands are discussed +in Section 3. +The arguments may be required or optional, according to which function +is given; again, they are discussed in Section 3 under each individual +function. +.LP +Tab characters and spaces at the beginning of lines are ignored. +.LP +.SH +1.1. Command-line Flags +.LP +Three flags are recognized on the command line: +.in +1i +.ti -.5i +.B +-n: +.R +tells +.ul +sed +not to copy all lines, but only those specified by +.ul +p +functions or +.ul +p +flags after +.ul +s +functions (see Section 3.3); +.ti -.5i +.B +-e: +.R +tells +.ul +sed +to take the next argument as an editing command; +.ti -.5i +.B +-f: +.R +tells +.ul +sed +to take the next argument as a file name; +the file should contain editing commands, one to a line. +.in -1i +.SH +1.2. Order of Application of Editing Commands +.LP +Before any editing is done (in fact, before any input file is +even opened), all the editing commands are compiled into +a form which will be moderately efficient during +the execution phase (when the commands are actually applied to +lines of the input file). +The commands are compiled in the order in which they are +encountered; this is generally the order in which they will +be attempted at execution time. +The commands are applied one at a time; the input to each command +is the output of all preceding commands. +.LP +The default linear order of application of editing commands can +be changed by the flow-of-control commands, +.ul +t +and +.ul +b +(see Section 3). +Even when the order of application is changed +by these commands, it is still true that the input line to any +command is the output of any previously applied command. +.SH +1.3. Pattern-space +.LP +The range of pattern matches is called the pattern space. +Ordinarily, the pattern space is one line of the input text, +but more than one line can be read into the pattern space +by using the +.ul +N +command (Section 3.6.). +.LP +.SH +1.4. Examples +.LP +Examples are scattered throughout the text. +Except where otherwise noted, +the examples all assume the following input text: +.LP +.in +.5i +.nf +In Xanadu did Kubla Khan +A stately pleasure dome decree: +Where Alph, the sacred river, ran +Through caverns measureless to man +Down to a sunless sea. +.in -.5i +.fi +.LP +(In no case is the output of the +.ul +sed +commands to be considered an improvement +on Coleridge.) +.LP +.SH +Example: +.LP +The command +.in +.5i +.LP +2q +.in -.5i +.LP +will quit after copying the first two lines of the input. +The output will be: +.LP +.in +.5i +.nf +In Xanadu did Kubla Khan +A stately pleasure dome decree: +.in -.5i +.fi +.LP +.SH +2. ADDRESSES: Selecting lines for editing +.LP +Lines in the input file(s) to which editing commands are +to be applied can be selected by addresses. +Addresses may be either line numbers or context addresses. +.LP +The application of a group of commands can be controlled by +one address (or address-pair) by grouping +the commands with curly braces (`{ }')(Sec. 3.6.). +.SH +2.1. Line-number Addresses +.LP +A line number is a decimal integer. +As each line is read from the input, a line-number counter +is incremented; +a line-number address matches (selects) the input +line which causes the internal counter to equal the +address line-number. +The counter runs cumulatively through multiple input files; +it is not reset when a new input file is opened. +.LP +As a special case, the character +$ +matches the last line of the last input file. +.SH +2.2. Context Addresses +.LP +A context address is a pattern (`regular expression') enclosed in slashes (`/'). +The regular expressions recognized by +.ul +sed +are constructed as follows: +.in +1i +.LP +.ti -.5i +1) +An ordinary character (not one of those discussed below) +is a regular expression, and matches that character. +.LP +.ti -.5i +2) +A circumflex `^' at the beginning of a regular expression +matches the null character at the beginning of a line. +.ti -.5i +3) +A dollar-sign `$' at the end of a regular expression +matches the null character at the end of a line. +.ti -.5i +4) +The characters `\en' match an imbedded newline character, +but not the newline at the end of the pattern space. +.ti -.5i +5) +A period `.' matches any character except the terminal newline +of the pattern space. +.ti -.5i +6) +A regular expression followed by an asterisk `*' matches any +number (including 0) of adjacent occurrences of the regular +expression it follows. +.ti -.5i +7) +A string of characters in square brackets `[ ]' matches any character +in the string, and no others. +If, however, the first character of the string is circumflex `^', +the regular expression matches any character +.ul +except +the characters in the string and the terminal newline of the pattern space. +.ti -.5i +8) +A concatenation of regular expressions is a regular expression +which matches the concatenation of strings matched by the +components of the regular expression. +.ti -.5i +9) +A regular expression between the sequences `\e(' and `\e)' is +identical in effect to the unadorned regular expression, but has +side-effects which are described under the +.ul +s +command below and specification 10) immediately below. +.ti -.5i +10) +The expression +.ul +`\|\ed' +means the same string of characters matched +by an expression enclosed in `\e(' and `\e)' +earlier in the same pattern. +Here +.ul +d +is a single digit; +the string specified is that beginning with the +\fId\|\fRth +occurrence of `\e(' counting from the left. +For example, the expression +`^\e(.*\e)\e1' matches a line beginning with +two repeated occurrences of the same string. +.ti -.5i +11) +The null regular expression standing alone (e.g., `//') is +equivalent to the last regular expression compiled. +.in -1i +.LP +To use one of the special characters (^ $ . * [ ] \e /) as a literal +(to match an occurrence of itself in the input), precede the +special character by a backslash `\e'. +.LP +For a context address to `match' the input requires that +the whole pattern within the address match some +portion of the pattern space. +.SH +2.3. Number of Addresses +.LP +The commands in the next section can have 0, 1, or 2 addresses. +Under each command the maximum number of allowed addresses is +given. +For a command to have more addresses than the maximum allowed +is considered an error. +.LP +If a command has no addresses, it is applied to every line +in the input. +.LP +If a command has one address, it is applied to all +lines which match that address. +.LP +If a command has two addresses, it is applied to the first +line which matches the first address, and to all subsequent lines +until (and including) the first subsequent line which matches +the second address. +Then an attempt is made on subsequent lines to again match the first +address, and the process is repeated. +.LP +Two addresses are separated by a comma. +.SH +Examples: +.LP +.nf +.in +.5i +.ta 1i 2i +/an/ matches lines 1, 3, 4 in our sample text +/an.*an/ matches line 1 +/^an/ matches no lines +/./ matches all lines +/\e./ matches line 5 +/r*an/ matches lines 1,3, 4 (number = zero!) +/\e(an\e).*\e1/ matches line 1 +.fi +.in 0 +.LP +.SH +3. FUNCTIONS +.LP +All functions are named by a single character. +In the following summary, the maximum number of allowable addresses +is given enclosed in parentheses, then the single character +function name, possible arguments enclosed in angles (< >), +an expanded English translation of the single-character name, +and finally a description of what each function does. +The angles around the arguments are +.ul +not +part of the argument, and should not be typed +in actual editing commands. +.SH +3.1. Whole-line Oriented Functions +.LP +.in +1i +.ti -.5i +(2)d -- delete lines +.if t .sp .5 +The +.ul +d +function deletes from the file (does not write to the output) +all those lines matched by its address(es). +.if t .sp .5 +It also has the side effect that no further commands are attempted +on the corpse of a deleted line; +as soon as the +.ul +d +function is executed, a new line is read from the input, and +the list of editing commands is re-started from the beginning +on the new line. +.ti -.5i +.if t .sp .5 +(2)n -- next line +.if t .sp .5 +The +.ul +n +function reads the next line from the input, replacing +the current line. +The current line is written to the output if it should +be. +The list of editing commands is continued +following the +.ul +n +command. +.if t .sp .5 +.nf +.in -.5i +(1)a\e +<text> -- append lines +.in +.5i +.fi +.if t .sp .5 +The +.ul +a +function causes the argument <text> to be written to the +output after the line matched by its address. +The +.ul +a +command is inherently multi-line; +.ul +a +must appear at the end of a line, and <text> may contain +any number of lines. +To preserve the one-command-to-a-line fiction, +the interior newlines must be hidden by a +backslash character (`\e') immediately preceding the +newline. +The <text> argument is terminated by the first unhidden +newline (the first one not immediately preceded +by backslash). +.if t .sp .5 +Once an +.ul +a +function is successfully executed, <text> will be +written to the output regardless of what later commands do to +the line which triggered it. +The triggering line may be +deleted entirely; <text> will still be written to the output. +.if t .sp .5 +The <text> is not scanned for address matches, and no editing +commands are attempted on it. +It does not cause any change in the line-number counter. +.ne 1i +.if t .sp .5 +.nf +.in -.5i +(1)i\e +<text> -- insert lines +.in +.5i +.fi +.if t .sp .5 +The +.ul +i +function behaves identically to the +.ul +a +function, except that <text> is written to the output +.ul +before +the matched line. +All other comments about the +.ul +a +function apply to the +.ul +i +function as well. +.if t .sp .5 +.nf +.in -.5i +(2)c\e +<text> -- change lines +.in +.5i +.fi +.if t .sp .5 +The +.ul +c +function deletes the lines selected by its address(es), +and replaces them with the lines in <text>. +Like +.ul +a +and +.ul +i, +.ul +c +must be followed by a newline hidden by a backslash; +and interior new lines in <text> must be hidden by +backslashes. +.if t .sp .5 +The +.ul +c +command may have two addresses, and therefore select a range +of lines. +If it does, all the lines in the range are deleted, but only +one copy of <text> is written to the output, +.ul +not +one copy per line deleted. +As with +.ul +a +and +.ul +i, +<text> is not scanned for address matches, and no +editing commands are attempted on it. +It does not change the line-number counter. +.if t .sp .5 +After a line has been deleted by a +.ul +c +function, no further commands are attempted on the corpse. +.if t .sp .5 +If text is appended after a line by +.ul +a +or +.ul +r +functions, and the line is subsequently changed, the text +inserted by the +.ul +c +function will be placed +.ul +before +the text of the +.ul +a +or +.ul +r +functions. +(The +.ul +r +function is described in Section 3.4.) +.if t .sp .5 +.in -1i +.ul +Note: +Within the text put in the output by these functions, +leading blanks and tabs will disappear, as always in +.ul +sed +commands. +To get leading blanks and tabs into the output, precede the first +desired blank or tab by a backslash; the backslash will not +appear in the output. +.SH +Example: +.LP +The list of editing commands: +.LP +.in +.5i +.nf +n +a\e +XXXX +d +.in -.5i +.fi +.LP +applied to our standard input, produces: +.LP +.in +.5i +.nf +In Xanadu did Kubhla Khan +XXXX +Where Alph, the sacred river, ran +XXXX +Down to a sunless sea. +.in -.5i +.fi +.LP +In this particular case, +the same effect would be produced by either +of the two following command lists: +.LP +.in +.5i +.nf +n n +i\e c\e +XXXX XXXX +d +.in -.5i +.fi +.LP +.in 0 +.SH +3.2. Substitute Function +.LP +One very important function changes parts of lines selected by +a context search within the line. +.if t .sp .5 +.in +1i +.ti -.5i +(2)s<pattern><replacement><flags> -- substitute +.if t .sp .5 +The +.ul +s +function replaces +.ul +part +of a line (selected by <pattern>) with <replacement>. +It can best be read: +.if t .sp .5 +.ti +1i +Substitute for <pattern>, <replacement> +.if t .sp .5 +The <pattern> argument contains a pattern, +exactly like the patterns in addresses (see 2.2 above). +The only difference between <pattern> and a context address is +that the context address must be delimited by slash (`/') characters; +<pattern> may be delimited by any character other than space or +newline. +.if t .sp .5 +By default, only the first string matched by <pattern> is replaced, +but see the +.ul +g +flag below. +.if t .sp .5 +The +<replacement> argument begins immediately after the +second delimiting character of <pattern>, and must be followed +immediately by another instance of the delimiting character. +(Thus there are exactly +.ul +three +instances of the delimiting character.) +.if t .sp .5 +The <replacement> is not a pattern, +and the characters which are special in patterns +do not have special meaning in <replacement>. +Instead, other characters are special: +.if t .sp .5 +.in +1i +.ti -.5i +& is replaced by the string matched by <pattern> +.if t .sp .5 +.ti -.5i +.ul +\ed +(where +.ul +d +is a single digit) is replaced by the \fId\fRth substring +matched by parts of <pattern> enclosed in `\e(' and `\e)'. +If nested substrings occur in <pattern>, the \fId\fRth +is determined by counting opening delimiters (`\e('). +.if t .sp .5 +As in patterns, special characters may be made +literal by preceding them with backslash (`\e'). +.if t .sp .5 +.in -1i +The <flags> argument may contain the following flags: +.if t .sp .5 +.in +1i +.ti -.5i +g -- substitute <replacement> for all (non-overlapping) +instances of <pattern> in the line. +After a successful substitution, the scan for the next +instance of <pattern> begins just after the end of the +inserted characters; characters put into the line from +<replacement> are not rescanned. +.if t .sp .5 +.ti -.5i +p -- print the line if a successful replacement was done. +The +.ul +p +flag causes the line to be written to the output if and only +if a substitution was actually made by the +.ul +s +function. +Notice that if several +.ul +s +functions, each followed by a +.ul +p +flag, successfully substitute in the same input line, +multiple copies of the line will be written to the +output: one for each successful substitution. +.if t .sp .5 +.ti -.5i +w <filename> -- write the line to a file if a successful +replacement was done. +The +.ul +w +flag causes lines which are actually substituted by the +.ul +s +function to be written to a file named by <filename>. +If <filename> exists before +.ul +sed +is run, it is overwritten; +if not, it is created. +.if t .sp .5 +A single space must separate +.ul +w +and <filename>. +.if t .sp .5 +The possibilities of multiple, somewhat different copies of +one input line being written are the same as for +.ul +p. +.if t .sp .5 +A maximum of 10 different file names may be mentioned after +.ul +w +flags and +.ul +w +functions (see below), combined. +.in 0 +.SH +Examples: +.LP +The following command, applied to our standard input, +.LP +.in +.5i +s/to/by/w changes +.in -.5i +.LP +produces, on the standard output: +.LP +.in +.5i +.nf +In Xanadu did Kubhla Khan +A stately pleasure dome decree: +Where Alph, the sacred river, ran +Through caverns measureless by man +Down by a sunless sea. +.fi +.in -.5i +.LP +and, on the file `changes': +.LP +.in +.5i +.nf +Through caverns measureless by man +Down by a sunless sea. +.fi +.in -.5i +.LP +If the nocopy option is in effect, the command: +.LP +.in +.5i +.nf +s/[.,;?:]/*P&*/gp +.fi +.in -.5i +.LP +produces: +.LP +.in +.5i +.nf +A stately pleasure dome decree*P:* +Where Alph*P,* the sacred river*P,* ran +Down to a sunless sea*P.* +.LP +.in -.5i +.fi +Finally, to illustrate the effect of the +.ul +g +flag, +the command: +.LP +.in +.5i +.nf +/X/s/an/AN/p +.in -.5i +.fi +.LP +produces (assuming nocopy mode): +.in +.5i +.LP +.nf +In XANadu did Kubhla Khan +.fi +.in -.5i +.LP +and the command: +.LP +.in +.5i +.nf +/X/s/an/AN/gp +.in -.5i +.fi +.LP +produces: +.LP +.in +.5i +.nf +In XANadu did Kubhla KhAN +.in -.5i +.fi +.LP +.in 0 +.SH +3.3. Input-output Functions +.LP +.in +1i +.ti -.5i +(2)p -- print +.if t .sp .5 +The print function writes the addressed lines to the standard output file. +They are written at the time the +.ul +p +function is encountered, regardless of what succeeding +editing commands may do to the lines. +.if t .sp .5 +.ti -.5i +(2)w <filename> -- write on <filename> +.if t .sp .5 +The write function writes the addressed lines to the file named +by <filename>. +If the file previously existed, it is overwritten; if not, it is created. +The lines are written exactly as they exist when the write function +is encountered for each line, regardless of what subsequent +editing commands may do to them. +.if t .sp .5 +Exactly one space must separate the +.ul +w +and <filename>. +.if t .sp .5 +A maximum of ten different files may be mentioned in write +functions and +.ul +w +flags after +.ul +s +functions, combined. +.if t .sp .5 +.ti -.5i +(1)r <filename> -- read the contents of a file +.if t .sp .5 +The read function reads the contents of <filename>, and appends +them after the line matched by the address. +The file is read and appended regardless of what subsequent +editing commands do to the line which matched its address. +If +.ul +r +and +.ul +a +functions are executed on the same line, +the text from the +.ul +a +functions and the +.ul +r +functions is written to the output in the order that +the functions are executed. +.if t .sp .5 +Exactly one space must separate the +.ul +r +and <filename>. +If a file mentioned by a +.ul +r +function cannot be opened, it is considered a null file, +not an error, and no diagnostic is given. +.if t .sp .5 +.in -1i +NOTE: +Since there is a limit to the number of files that can be opened +simultaneously, care should be taken that no more than ten +files be mentioned in +.ul +w +functions or flags; that number is reduced by one if any +.ul +r +functions are present. +(Only one read file is open at one time.) +.in 0 +.SH +Examples +.LP +Assume that the file `note1' +has the following contents: +.LP +.in +1i +Note: Kubla Khan (more properly Kublai Khan; 1216-1294) +was the grandson and most eminent successor of Genghiz +(Chingiz) Khan, and founder of the Mongol dynasty in China. +.LP +.in 0 +Then the following command: +.LP +.nf +.in +.5i +/Kubla/r note1 +.in -.5i +.fi +.LP +produces: +.LP +.nf +.in +.5i +In Xanadu did Kubla Khan +.in +.5i +.fi +Note: Kubla Khan (more properly Kublai Khan; 1216-1294) +was the grandson and most eminent successor of Genghiz +(Chingiz) Khan, and founder of the Mongol dynasty in China. +.in -.5i +.nf +A stately pleasure dome decree: +Where Alph, the sacred river, ran +Through caverns measureless to man +Down to a sunless sea. +.in -.5i +.fi +.LP +.in 0 +.SH +3.4. +Multiple Input-line Functions +.LP +Three functions, all spelled with capital letters, deal +specially with pattern spaces containing imbedded newlines; +they are intended principally to provide pattern matches across +lines in the input. +.if t .sp .5 +.in +1i +.ti -.5i +(2)N -- Next line +.if t .sp .5 +The next input line is appended to the current line in the +pattern space; the two input lines are separated by an imbedded +newline. +Pattern matches may extend across the imbedded newline(s). +.if t .sp .5 +.ti -.5i +(2)D -- Delete first part of the pattern space +.if t .sp .5 +Delete up to and including the first newline character +in the current pattern space. +If the pattern space becomes empty (the only newline +was the terminal newline), +read another line from the input. +In any case, begin the list of editing commands again +from its beginning. +.if t .sp .5 +.ti -.5i +(2)P -- Print first part of the pattern space +.if t .sp .5 +Print up to and including the first newline in the pattern space. +.if t .sp .5 +.in 0 +The +.ul +P +and +.ul +D +functions are equivalent to their lower-case counterparts +if there are no imbedded newlines in the pattern space. +.in 0 +.SH +3.5. Hold and Get Functions +.LP +Four functions save and retrieve part of the input for possible later +use. +.if t .sp .5 +.in 1i +.ti -.5i +(2)h -- hold pattern space +.if t .sp .5 +The +.ul +h +functions copies the contents of the pattern space +into a hold area (destroying the previous contents of the +hold area). +.if t .sp .5 +.ti -.5i +(2)H -- Hold pattern space +.if t .sp .5 +The +.ul +H +function appends the contents of the pattern space +to the contents of the hold area; the former and new contents +are separated by a newline. +.if t .sp .5 +.ti -.5i +(2)g -- get contents of hold area +.if t .sp .5 +The +.ul +g +function copies the contents of the hold area into +the pattern space (destroying the previous contents of the +pattern space). +.if t .sp .5 +.ti -.5i +(2)G -- Get contents of hold area +.if t .sp .5 +The +.ul +G +function appends the contents of the hold area to the +contents of the pattern space; the former and new contents are separated by +a newline. +.if t .sp .5 +.ti -.5i +(2)x -- exchange +.if t .sp .5 +The exchange command interchanges the contents +of the pattern space and the hold area. +.in 0 +.SH +Example +.LP +The commands +.nf +.if t .sp .5 + 1h + 1s/ did.*// + 1x + G + s/\en/ :/ +.if t .sp .5 +.fi +applied to our standard example, produce: +.nf +.if t .sp .5 + In Xanadu did Kubla Khan :In Xanadu + A stately pleasure dome decree: :In Xanadu + Where Alph, the sacred river, ran :In Xanadu + Through caverns measureless to man :In Xanadu + Down to a sunless sea. :In Xanadu +.if t .sp .5 +.fi +.SH +3.6. Flow-of-Control Functions +.LP +These functions do no editing on the input +lines, but control the application of functions +to the lines selected by the address part. +.if t .sp .5 +.in +1i +.ti -.5i +(2)! -- Don't +.if t .sp .5 +The +.ul +Don't +command causes the next command +(written on the same line), to be applied to all and only those input lines +.ul +not +selected by the adress part. +.if t .sp .5 +.ti -.5i +(2){ -- Grouping +.if t .sp .5 +The grouping command `{' causes the +next set of commands to be applied +(or not applied) as a block to the +input lines selected by the addresses +of the grouping command. +The first of the commands under control of the grouping +may appear on the same line as the +`{' or on the next line. +.LP +The group of commands is terminated by a +matching `}' standing on a line by itself. +.LP +Groups can be nested. +.ti -.5i +.if t .sp .5 +(0):<label> -- place a label +.if t .sp .5 +The label function marks a place in the list +of editing commands which may be referred to by +.ul +b +and +.ul +t +functions. +The <label> may be any sequence of eight or fewer characters; +if two different colon functions have identical labels, +a compile time diagnostic will be generated, and +no execution attempted. +.if t .sp .5 +.ti -.5i +(2)b<label> -- branch to label +.if t .sp .5 +The branch function causes the sequence of editing commands being +applied to the current input line to be restarted immediately +after the place where a colon function with the same <label> +was encountered. +If no colon function with the same label can be found after +all the editing commands have been compiled, a compile time diagnostic +is produced, and no execution is attempted. +.if t .sp .5 +A +.ul +b +function with no <label> is taken to be a branch to the end of the +list of editing commands; +whatever should be done with the current input line is done, and +another input line is read; the list of editing commands is restarted from the +beginning on the new line. +.if t .sp .5 +.ti -.5i +(2)t<label> -- test substitutions +.if t .sp .5 +The +.ul +t +function tests whether +.ul +any +successful substitutions have been made on the current input +line; +if so, it branches to <label>; +if not, it does nothing. +The flag which indicates that a successful substitution has +been executed is reset by: +.if t .sp .5 +.in +1i +1) reading a new input line, or +.br +2) executing a +.ul +t +function. +.if t .sp .5 +.in 0 +.SH +3.7. Miscellaneous Functions +.LP +.in +1i +.ti -.5i +(1)= -- equals +.if t .sp .5 +The = function writes to the standard output the line number of the +line matched by its address. +.if t .sp .5 +.ti -.5i +(1)q -- quit +.if t .sp .5 +The +.ul +q +function causes the current line to be written to the +output (if it should be), any appended or read text to be written, and +execution to be terminated. +.in 0 +.SH +.SH +Reference +.IP [1] +Ken Thompson and Dennis M. Ritchie, +.ul +The UNIX Programmer's Manual. +Bell Laboratories, 1978. |