How to grep a tab on Linux? Including ‘t’ seems not working.
grep can grep tabs. The problem is likely the tab is not passed to grep.
If you are using Bash, you can use ANSI-C quoting to pass the “tab” to grep:
$ grep $'t' file.txt
Or, use Perl-style regex (only for GNU grep) to grep tab:
$ grep -P 't' file.txt
I would like to know whether a function, say f1(), has already been defined in Bash. How should I do it? You can use the type -t to get a string of the type of the name: If the -t option is used, type prints a string which is one of alias, keyword, function, builtin,…
I connect a USB keyboard to my laptop so the internal keyboard is not used anymore. But I may press some keys by accident. How to disable the laptop internal keyboard? I am working on Linux. This post introduces how to disable laptop’s internal keyboard on Linux: How to Disable and Enable Laptop Keyboard in…
I have 2 branches: dev and master. I have commits in dev like this: c0–>c1–>c2–>c3–>c4 Commits in master like this: c0–>c5–>c6 c2 and c3 fix a bug. Now, I want to merge commit c2 and c3 that fix the bug to the master branch, but I do not want to merge all the commits (e.g….
How to make fdisk -l display partition sizes by bytes instead of sectors? fdisk does not have such options as far as I know. However, good news is that you can use parted: # parted -l It will print partition info like # parted -l Model: Linux device-mapper (linear) (dm) Disk /dev/mapper/fedora_vm235-swap: 2164MB Sector size…
I would like to open files by open() directly. But how to get a FILE pointer from a file descriptor in C on Linux? And how to do the reverse direction: get a file descriptor from a FILE pointer? Get a FILE pointer from a file descriptor (e.g. fd) in C on Linux: FILE *file…
I have a large IMAP email account which contains many emails in a rich structure of directories. How to back up the whole IMAP account to my local computer? The requirements: Automatically downloading these files. There are many directories, and copying-pasting emails will take too much time. Keep the directory structures which are used to…