Re: Write multiple backslashes

On Mar 8, 2017 6:27 AM, "Jason Pruim" <pruimj@gmail.com> wrote: Sent from my iPhone > On Mar 8, 2017, at 4:48 AM, Danny <mynixmail@gmail.com> wrote: > > Hi, > > I have a file in which I need to interchange two regular expressions every hour > depending on what data will be processed. In other words, I will replace the one > regular expression with the other (they are never together in the same file). > This file is a configuration file for attatched hardware (not written by myself > but by the hardware manufacturer). > > Below is what it should look like in the file: > IGNORE_TMP=^()$ > or > IGNORE_TMP=^(\\*.*\\*)$" (Yes, this one has 2 backslashes) > > Now, the first regular expression I can write to the file like this with no > problems: > $first_regexp = "/IGNORE_TMP=\\^\\(\\)\\$/" ; > which will give me: > IGNORE_TMP=^()$. > > However, I cannot seem to get it right to write the second regular expression > correctly to get 2 backlashes. I can get 1 with no problem: > $second_regexp = "IGNORE_TMP=^(\\*.*\\*)$" ; I'm no regard expert but don't you have to escape it for each one? Something like $second_rexexp = "ignore_tmp=^(\\\\*.*\\\\*)$"; I could be way off base though... Yes that's true but only because it is a double quoted string, meaning backslashes are treated as escape sequences. You could also just use a single quoted string. $second_regexp = 'IGNORE_TMP=^(\\*.*\\*)$'; > ### Here is just the rest of the code for reference ### > $block_file = file_get_contents ( $tmp_file ) ; > $block_regexp = preg_replace ( $old_block, $new_block, $block_file ) ; > file_put_contents ( $tmp_file, $block_regexp ) ; > $remove_blank_lines = exec ( 'sed -i "/^[[:space:]]*$/d" /etc/scripts/motor_control/temperature.conf' ) ; > ####################################################### > > Any pointers? > > Thank you > > Danny > > -- > PHP General Mailing List (http://www.php.net/) > To unsubscribe, visit: http://www.php.net/unsub.php > -- PHP General Mailing List (http://www.php.net/) To unsubscribe, visit: http://www.php.net/unsub.php