[Go to CFHT Home Page] Man Pages
Back to Software Index  BORDER=0Manpage Top Level
    sed(1B) manual page Table of Contents

Name

sed - stream editor

Synopsis

sed [ -n ] [ -e script ] [ -f sfilename ] [ filename ] ...

Availability

SUNWscpu

Description

sed copies the filenames (standard input default) to the standard output, edited according to a script of commands.

Options

-n
Suppress the default output.
-e script
script is an edit command for sed. If there is just one -e option and no -f options, the -e flag may be omitted.
-f sfilename
Take the script from sfilename.

Usage

sed Scripts

sed " scripts" consist of editing commands, one per line, of the following form:

[ address [, address ] ] function [ arguments ]

In normal operation sed cyclically copies a line of input into a pattern space (unless there is something left after a D command), sequentially applies all commands with addresses matching that pattern space until reaching the end of the script, copies the pattern space to the standard output (except under -n), and finally, deletes the pattern space.

Some commands use a hold space to save all or part of the pattern space for subsequent retrieval.

An address is either:

a decimal number linecount, which is cumulative across input files;
a
$, which addresses the last input line;
or a context address, which is a
/regular expression/ as described on the regexp(5) manual page, with the following exceptions:
\?RE?
In a context address, the construction \ ?regular expression?, where ? is any character, is identical to /regular expression/. Note: in the context address \xabc\xdefx, the second x stands for itself, so that the regular expression is abcxdef.
\n
Matches a NEWLINE embedded in the pattern space. .
  • Matches any character except the NEWLINE ending the pattern space.
    • null
    A command line with no address selects every pattern space.
    address
    Selects each pattern space that matches.
    address1 ,address2
    Selects the inclusive range from the first pattern space matching addrress1 to the first pattern space matching address2. Selects only one line if address1 is greater than or equal to address2.

    Comments

    If the first nonwhite character in a line is a ‘#’ (pound sign), sed treats that line as a comment, and ignores it. If, however, the first such line is of the form:
    #n

    sed runs as if the -n flag were specified.

    Functions

    The maximum number of permissible addresses for each function is indicated in parentheses in the list below.

    An argument denoted text consists of one or more lines, all but the last of which end with \ to hide the NEWLINE . Backslashes in text are treated like backslashes in the replacement string of an s command, and may be used to protect initial SPACE and TAB characters against the stripping that is done on every script line.

    An argument denoted rfilename or wfilename must terminate the command line and must be preceded by exactly one SPACE . Each wfilename is created before processing begins. There can be at most 10 distinct wfilename arguments.

    (1)a\
    text
    Append: place text on the output before reading the next input line.
    (2)b label
    Branch to the ‘:’ command bearing the label. Branch to the end of the script if label is empty.
    (2)c\
    text
    Change: delete the pattern space. With 0 or 1 address or at the end of a 2 address range, place text on the output. Start the next cycle.
    (2)d
    Delete the pattern space. Start the next cycle.
    (2)D
    Delete the initial segment of the pattern space through the first NEWLINE . Start the next cycle.
    (2)g
    Replace the contents of the pattern space by the contents of the hold space.
    (2)G
    Append the contents of the hold space to the pattern space.
    (2)h
    Replace the contents of the hold space by the contents of the pattern space.
    (2)H
    Append the contents of the pattern space to the hold space.
    (1)i\
    text
    Insert: place text on the standard output.
    (2)l
    List the pattern space on the standard output in an unambiguous form. Non-printing characters are spelled in two digit ASCII and long lines are folded.
    (2)n
    Copy the pattern space to the standard output. Replace the pattern space with the next line of input.
    (2)N
    Append the next line of input to the pattern space with an embedded newline. (The current line number changes.)
    (2)p
    Print: copy the pattern space to the standard output.
    (2)P
    Copy the initial segment of the pattern space through the first NEWLINE to the standard output.
    (1)q
    Quit: branch to the end of the script. Do not start a new cycle.
    (2)r rfilename
    Read the contents of rfilename. Place them on the output before reading the next input line.
    (2)s/regular expression/replacement/flags
    Substitute the replacement string for instances of the regular expression in the pattern space. Any character may be used instead of ‘/’. For a fuller description see regexp(5) . flags is zero or more of:
    n
    n= 1 - 512. Substitute for just the nth occurrence of the regularexpression.
    g
    Global: substitute for all nonoverlapping instances of the regular expression rather than just the first one.
    p
    Print the pattern space if a replacement was made.
    w wfilename
    Write: append the pattern space to wfilename if a replacement was made.
    (2)t label
    Test: branch to the ‘:’ command bearing the label if any substitutions have been made since the most recent reading of an input line or execution of a t. If label is empty, branch to the end of the script.
    (2)w wfilename
    Write: append the pattern space to wfilename.
    (2)x
    Exchange the contents of the pattern and hold spaces.
    (2)y/string1/string2/
    Transform: replace all occurrences of characters in string1 with the corresponding character in string2. The lengths of string1 and string2 must be equal.
    (2)! function
    Do not: apply the function (or group, if function is ‘{’) only to lines not selected by the address(es).
    (0): label
    This command does nothing; it bears a label for b and t commands to branch to. Note: the maximum length of label is seven characters.
    (1)=
    Place the current line number on the standard output as a line.
    (2){
    Execute the following commands through a matching ‘}’ only when the pattern space is selected. Commands are separated by ‘;’.
  • An empty command is ignored.

    • Diagnostics

    Too many commands
    The command list contained more than 200 commands.
    Too much command text
    The command list was too big for sed to handle. Text in the a, c, and i commands, text read in by r commands, addresses, regular expressions and replacement strings in s commands, and translation tables in y commands all require sed to store data internally.
    Command line too long
    A command line was longer than 4000 characters.
    Too many line numbers
    More than 256 decimal number linecounts were specified as addresses in the command list.
    Too many files in w commands
    More than 10 different files were specified in w commands or w options for s commands in the command list.
    Too many labels
    More than 50 labels were specified in the command list.
    Unrecognized command
    A command was not one of the ones recognized by sed.
    Extra text at end of command
    A command had extra text after the end.
    Illegal line number
    An address was neither a decimal number linecount, a $, nor a context address.
    Space missing before filename
    There was no space between a r or w command, or the w option for a s command, and the filename specified for that command.
    Too many {’s
    There were more { than } in the list of commands to be executed.
    Too many }’s
    There were more } than { in the list of commands to be executed.
    No addresses allowed
    A command that takes no addresses had an address specified.
    Only one address allowed
    A command that takes one address had two addresses specified.
    ‘\digit’ out of range
    The number in a \n item in a regular expression or a replacement string in a s command was greater than 9.
    Bad number
    One of the endpoints in a range item in a regular expression (that is, an item of the form {n} or {n,m}) was not a number.
    Range endpoint too large
    One of the endpoints in a range item in a regular expression was greater than 255.
    More than 2 numbers given in \{ \}
    More than two endpoints were given in a range expression.
    } expected after \
    A \ appeared in a range expression and was not followed by a }.
    First number exceeds second in \{ \}
    The first endpoint in a range expression was greater than the second.
    Illegal or missing delimiter
    The delimiter at the end of a regular expression was absent.
    \( \) imbalance
    There were more \( than \), or more \) than \(, in a regular expression.
    [ ] imbalance
    There were more [ than ], or more ] than [, in a regular expression.
    First RE may not be null
    The first regular expression in an address or in a s command was null (empty).
    Ending delimiter missing on substitution
    The ending delimiter in a s command was absent.
    Ending delimiter missing on string
    The ending delimiter in a y command was absent.
    Transform strings not the same size
    The two strings in a y command were not the same size.
    Suffix too large - 512 max
    The suffix in a s command, specifying which occurrence of the regular expression should be replaced, was greater than 512.
    Label too long
    A label in a command was longer than 8 characters.
    Duplicate labels
    The same label was specified by more than one : command.
    File name too long
    The filename specified in a r or w command, or in the w option for a s command, was longer than 1024 characters.
    Output line too long.
    An output line was longer than 4000 characters long.
    Too many appends or reads after line n
    More than 20 a or r commands were to be executed for line n.
    Hold space overflowed.
    More than 4000 characters were to be stored in the hold space.

    Files

    usr/ucb/sed
    BSD sed

    See Also

    awk(1) , grep(1) , lex(1) , regexp(5)

    Bugs

    There is a combined limit of 200 -e and -f arguments. In addition, there are various internal size limits which, in rare cases, may overflow. To overcome these limitations, either combine or break out scripts, or use a pipeline of sed commands.

    Table of Contents