> For the complete documentation index, see [llms.txt](https://www.shellspells.net/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://www.shellspells.net/linux/file-ops/search/filename.md). # Filename ## Filenames

Command	Description
`grep -rli file*`	Pattern match
`grep -rli "filename" /path/to/search`	Recursive
`ls -R [directory] \| grep "filename"`	Recursive
`find / -a -iname "filename"`	Case insensitive
`find / -a -type f -name password.txt`	Recursive exact match
`find / -a -name "pat*tern"`	Pattern match "pat" and ending with "tern"
`find / -a -type d -name config`	Exact directory match
`find / -a -type d -name "\687-250\"`	Pattern directory match
`find / -a -regex "regex_pattern"`	Regex
`locate "[filename]"`	Uses a database updated by `updatedb` to quickly locate files
`locate -i "[filename]"`	Case-insensitive

Use extended regex syntax: ```bash find / -a -regextype egrep -regex "pat.+?ern" ``` Use Perl regex syntax: ```bash find / -a -regextype perl -regex "^user_[0-9]+.sh$" ``` Uses `xargs` for efficiency with a large number of files ```bash find / -a -type f -print0 | xargs -0 grep -l "[string]" ``` Finds files by name and then executes `ls -lh`: ```bash find / -a -type f -name "[filename]" -exec ls -lh {} + ``` Find development tools and supported languages: ```bash find / -a -name perl* find / -a -name python* find / -a -name gcc* ``` ## File Extensions

Command	Description
`ls [directory]/*.ext`	Not Recursive
`find / -a -type f $ -name ".txt" -o -name ".sh" $`	Multiple file extensions.
`find / -a -type f -name "*.txt"`	Recursive
`find / -a -type f -iname "*.txt"`	Case-insensitive.
`find / -a -type f -regex ".*\.txt"`	Use regular expressions.
`find / -a -regextype posix -regex ".+\.log$"`	Matches all files ending with .log, using POSIX regex syntax.
`grep -rli "\.txt$" /path/to/search`	Recursive
`grep -rli --include=\*.ext "pattern" [directory]`	Recursively searches for files with the `.ext` extension containing "pattern" in the specified directory.

## Search Multiple Dirs

Command	Description
`find /opt /usr /var -a -type f -name foo.scala`	Search specific directories
`find /directory* -name foo.txt`	Wildcard

Loop: Iterates through each directory and runs the find command inside each, effectively searching them all. ```bash for dir in /path/to/directory1 /path/to/directory2 ; do find "$dir" -name your_search_term done ``` ## Inverse

Command	Description
`grep -L`	Lists files that do not contain a specified pattern.
`ls / \| grep -v "[pattern]"`	Lists files in the root directory that do not match the specified pattern.
`find / -a -not -name "[pattern]"`	Finds files not matching a specific pattern.
`find / -a -type f -not -name "*.html"`	Finds files that do not end in ".html".
`find / -a ! -name "[pattern]"`	An alternative to `-not`, finds files not matching a specific pattern.
`find / -a ! -name "pattern1" ! -name "pattern2"`	Finds files not matching multiple patterns.
`find / -a -type f ! -exec grep -q "[pattern]" {} \; -print`	Finds files that do not contain a specified pattern using `-exec`.
`find / -a -type f -print0 \| xargs -0 grep -L "[pattern]"`	Finds files that do not contain a specified pattern using `xargs`.
`awk '!/[pattern]/' [file]`	Uses `awk` to print lines from a file that do not match a specific pattern.
`sed -n '/[pattern]/!p' [file]`	Uses `sed` to print lines from a file that do not match a specific pattern.

## Weird Filenames

Command	Description
`find / -a -type d -name " \*" -exec ls -ladtri {} 2>/dev/null +`	Directories with a space
`find / -a -type f -name " \*" -exec ls -latriQ {} 2>/dev/null +`	Files with a space
`find / -a -type f -name '[![:alnum:]_\-\.]'`	Files with non-alphanumeric characters in their filenames.
`find / -a -type f -regex '.[^[:alnum:]_\-\.].'`	Files with non-alphanumeric characters in their filenames using regex.

## Executables

Command	Description
`which grep`	Single binary
`which python java gcc`	Multiple binaries
`type ls`	Shows how the command is interpreted by the shell.
`command -v ls`	Shows how the command is interpreted by the shell.
`which -a python`	All instances of "python" in the path.

Command	Description
`ls [directory]/*.ext`	Not Recursive
`find / -a -type f \( -name ".txt" -o -name ".sh" \)`	Multiple file extensions.
`find / -a -type f -name "*.txt"`	Recursive
`find / -a -type f -iname "*.txt"`	Case-insensitive.
`find / -a -type f -regex ".*\.txt"`	Use regular expressions.
`find / -a -regextype posix -regex ".+\.log$"`	Matches all files ending with .log, using POSIX regex syntax.
`grep -rli "\.txt$" /path/to/search`	Recursive
`grep -rli --include=\*.ext "pattern" [directory]`	Recursively searches for files with the `.ext` extension containing "pattern" in the specified directory.