32v 1m sed
SED(1) UNIX Programmer's ManualSED(1)
Contents
NAME
sed - stream editor
SYNOPSIS
sed [ -n ] [ -e script ] [ -f sfile ] [ file ] ...
DESCRIPTION
_S_e_d copies the named _f_i_l_e_s (standard input default) to the standard output, edited according to a script of commands. The -f option causes the script to be taken from file _s_f_i_l_e; these options accumulate. If there is just one -e option and no -f's, the flag -e may be omitted. The -n option suppresses the default output.
A script consists 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), applies in sequence all commands whose addresses select that pattern space, and at the end of the script copies the pattern space to the standard output (except under -n) and deletes the pattern space.
An address is either a decimal number that counts input lines cumulatively across files, a `$' that addresses the last line of input, or a context address, `/regular expression/', in the style of _e_d(1) modified thus:
The escape sequence `\n' matches a newline embedded in the pattern space.
A command line with no addresses selects every pattern space.
A command line with one address selects each pattern space that matches the address.
A command line with two addresses selects the inclusive range from the first pattern space that matches the first address through the next pattern space that matches the second. (If the second address is a number less than or equal to the line number first selected, only one line is selected.) Thereafter the process is repeated, looking again for the first address.
Editing commands can be applied only to non-selected pattern spaces by use of the negation function `!' (below).
In the following list of functions the maximum number of permissible addresses for each function is indicated in parentheses.
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 blanks and tabs against the stripping that is done on every script line.
An argument denoted rfile or wfile must terminate the command line and must be preceded by exactly one blank. Each wfile is created before processing begins. There can be at most 10 distinct wfile 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 _l_a_b_e_l. If _l_a_b_e_l is empty, branch to the end of the script.
(2)c\ _t_e_x_t Change. Delete the pattern space. With 0 or 1 address or at the end of a 2-address range, place _t_e_x_t 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 con- tents 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\ _t_e_x_t Insert. Place _t_e_x_t on the standard output.
(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 _r_f_i_l_e Read the contents of _r_f_i_l_e. Place them on the output before reading the next input line.
(2)s/_r_e_g_u_l_a_r _e_x_p_r_e_s_s_i_o_n/_r_e_p_l_a_c_e_m_e_n_t/_f_l_a_g_s Substitute the _r_e_p_l_a_c_e_m_e_n_t string for instances of the _r_e_g_u_l_a_r _e_x_p_r_e_s_s_i_o_n in the pattern space. Any character may be used instead of `/'. For a fuller description see _e_d(1). _F_l_a_g_s is zero or more of
g Global. Substitute for all nonoverlapping instances of the _r_e_g_u_l_a_r _e_x_p_r_e_s_s_i_o_n rather than just the first one.
p Print the pattern space if a replacement was made.
w _w_f_i_l_e Write. Append the pattern space to _w_f_i_l_e if a replacement was made.
(2)t _l_a_b_e_l Test. Branch to the `:' command bearing the _l_a_b_e_l if any substitutions have been made since the most recent reading of an input line or execution of a `t'. If _l_a_b_e_l is empty, branch to the end of the script.
(2)w _w_f_i_l_e Write. Append the pattern space to _w_f_i_l_e.
(2)x Exchange the contents of the pattern and hold spaces.
(2)y/_s_t_r_i_n_g_1/_s_t_r_i_n_g_2/ Transform. Replace all occurrences of characters in _s_t_r_i_n_g_1 with the corresponding character in _s_t_r_i_n_g_2. The lengths of _s_t_r_i_n_g_1 and _s_t_r_i_n_g_2 must be equal.
(2)! _f_u_n_c_t_i_o_n Don't. Apply the _f_u_n_c_t_i_o_n (or group, if _f_u_n_c_t_i_o_n is `{') only to lines _n_o_t selected by the address(es).
(0): _l_a_b_e_l This command does nothing; it bears a _l_a_b_e_l for `b' and `t' commands to branch to.
(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.
(0) An empty command is ignored.
