replacing a path with sed

Question

How can I use sed to replace this line

char * path_list_[1] = { "/some/random/path" };

with this line

char * path_list_[2] = { "lib/foo", "lib/bar" };

in a file named source.c

Notes:
* The path is really random.
* Your solution should only change this line in source.c
* I'm only interested in a sed oneliner.

You can use this Python regex as a starting point:

text = re.sub('static const char \* path_list_\[1\] = \{ "[^"]*" \};', 
    'static const char * path_list_[2] = { "lib/sun", "lib/matlab" };', text)

Answer 1

Try this:

sed -e 's/=\s*{\s*"[^"]*"\s*};/= { "lib\/foo", "lib\/bar"};/' source.c | sed -e 's/path_list_\[1\]/path_list_[2]/'

Answer 2

First, find a character that will not appear in your path or your replacement (in general # is a good first approximation, but...).

Then:

sed 's#_.1. = {[^}]*}#_[2] = { "your/first", "and/your/second" }#'

Note that the first character after the s is your separator, there is no requirement for it to be /, it's just traditionally "the character I won't need".

EDIT: Seems as if sed doesn't understand + as "one or more". Use * (zero or more) instead.

Answer 3

$ cat file
aaaa
char * path_list_[1] = { "/some/random/path" };
zzzz

$ sed '/char/s@1\]@2]@;s@{.*}.*$@{\"lib\/foo", "lib\/bar"}@' file
aaaa
char * path_list_[2] = {"lib/foo", "lib/bar"}
zzzz

Answer 4

Assuming that you want to replace string variables named path_list_, and only those.

sed '/path_list_/s@1\]@2]@; /path_list_.*\[.*{/s@\".*\"@\"lib\/foo", "lib\/bar"@'

This replaces only the first 2 lines from the following input.

char * path_list_[1] = { "/some/random/path" };
char * path_list_[1] = {"/some/random/path"};
char * not_replaced[1] = { "/some/random/path" };
char * not_replaced[1] = {"/some/random/path"};
char * path_list_ = {"/some/random/path"};
path_list_[1] = "/some/random/path";

Answer 5

Based on the Python regex you gave:

echo 'char * path_list_[1] = { "/some/random/path" };' | \
    sed -E -e 's/char \* path_list_\[1\] = \{ "[^"]*" \};/char * path_list_[2] = { "lib\/sun", "lib\/matlab" };/'

outputs

char * path_list_[2] = { "lib/sun", "lib/matlab" };

or alternately

echo 'static const char * path_list_[1] = { "/some/random/path" };' | \
    sed -E -e 's/static const char \* path_list_\[1\] = \{ "[^"]*" \};/static const char * path_list_[2] = { "lib\/sun", "lib\/matlab" };/'

outputs

static const char * path_list_[2] = { "lib/sun", "lib/matlab" };

(This is done using the FreeBSD-type sed included in Mac OS X.)

Answer 6

sed -e 's@char \* path_list_\[1\] = { "[^"]*" };@char * path_list_[2] = { "lib/foo", "lib/bar" };@g'

Answer 7

sed -re 's/^(char \* path_list_\[)1(\] = \{ ")[^"]*(" \})\W*$/\12\2\/lib\/foo", "\/lib\/bar\3/' source.c