Linux – How to find file with name=“php.ini” on linux using grep command

Try

find /srv/www/*/htdocs/system/application/ -name "*.php" -exec grep "debug (" {} \; -print

This should recursively search the folders under application for files with .php extension and pass them to grep.

An optimization on this would be to execute:

find /srv/www/*/htdocs/system/application/ -name "*.php" -print0 | xargs -0 grep -H "debug ("

This uses xargs to pass all the .php files output by find as arguments to a single grep command; e.g., grep "debug (" file1 file2 file3. The -print0 option of find and -0 option of xargs ensure the spaces in file and directory names are correctly handled. The -H option passed to grep ensures that the filename is printed in all situations. (By default, grep prints the filename only when multiple arguments are passed in.)

From man xargs:

-0

Input items are terminated by a null character instead of by whitespace, and the quotes and backslash are not special (every character is taken literally).  Disables the end of file string, which is treated like any other argument.  Useful when input items might contain white space, quote marks, or backslashes.  The GNU find -print0 option produces input suitable for this mode.

Are you looking for "howdy doody" in the filename, or within the file?

# find files with "howdy doody" in the filename
find * -name "*howdy doody*" -print0 | xargs -0 ...

xargs is what you need to use to split the null-terminated output from find -print0. In your example, the echo is extraneous; don't bother with it.

# find files containing "howdy doody"
find * -print0 | xargs -0 grep -l "howdy doody"

# find files containing "howdy doody" and do further processing

# multiple xargs version
find * -print0 | xargs -0 grep -l "howdy doody" | xargs -i{} do-something "{}"

# "sh -c" version
find * -print0 | xargs -0 -i{} sh -c 'grep -l "howdy doody" "{}" && do-something "{}"'

# notes: 
#   "sh -c" allows us to run a complex command with a single xargs
#   "{}" handles spaces-in-filename
#   handles any &&, ||, | command linking

You can also run your command directly from the find with -exec. The difference is that find -exec runs the command once per file found; xargs adds filenames to the end of the command (up to system limit), so it runs the command fewer times. You can simulate this with xargs -n1 to force xargs to only run one command per input.

# grep once per file
find * -exec grep -l "howdy doody" {} \; | ...