When braces are used, the matching ending brace is the first ‘}’ not escaped by a backslash or within a quoted string, and not within an embedded arithmetic expansion, command substitution, or parameter expansion. Remove QuoteCls Quote; variable as single quoted string has no inner states. ...
2. Escape every char with a backslash This works for all characters except newline. For newline characters use single or double quotes. Empty strings must still be handled - replace with "" \I\'\m\ \a\ \s\@\f\e\ \$\t\r\i\n\g\ \w\h\i\c\h\ \e\n\d\s\ \i\n\ \n\...
Single quotes can't be nested. You have to end the single quotes, add an escaped or quoted single quote, than open a new quoted string. sed 's/$/'\'',/' sed 's/$/'"'"',/' You can also switch the quotes and use double quotes for the whole expression: sed "s/$/',/" ...
I consider this to be very useful. If you're new to regex, note especially the section about backreferences in replacements. You may wish to check the section in the regex HOWTO about Search and Replace as well.How to awkThe sed section needed a little disclaimer. The awk section needs...
//: This is the pattern substitution operator. It tells Bash to replace all instances of a given pattern with a new string. \": This is the matched pattern, simply the backslash-escaped double quote character (").The Backslash is used to escape double quotesso that Bash treats them as ...
A double quote may be quoted within double quotes by preceding it with a backslash. If enabled, history expansion will be performed unless an ! appearing in double quotes is escaped using a backslash. The back- slash preceding the ! is not removed. The special parameters * and @ have ...
Words of the form $'string' are treated specially. The word expands to string, with backslash-escaped characters replaced as specified by the ANSI C standard. Backslash escape sequences, if present, are decoded as follows: \nnewline\rcarriagereturn\thorizontal tab\'single quote ...
把 newline 赋值为 $'\n'，就能获取到换⾏符⾃⾝。查看 man bash 对这个写法的说明如下：Words of the form $'string' are treated specially. The word expands to string, with backslash-escaped characters replaced as specified by the ANSI C standard. Backslash escape sequences, if present, ...
12.4. Control bash loop with Here is a example of while loop controlled by standard input. Until the redirection chain from STDOUT to STDIN to the read command exists the while loop continues. #!/bin/bash# This bash script will locate and replace spaces ...
and displaying only parent processes of a specific PID. Meanwhile,'$$'is a unique shell variable that bash will replace with its own PID when evaluating command line arguments. It is quoted once to prevent local shell interpretation but not doubly quoted or escaped to enable interpretation by ...