unix 800

  1. Check if a directory exists in a shell script
  2. How can I pretty-print JSON in a (Unix) shell script?
  3. How to concatenate string variables in Bash
  4. In the shell, what does “ 2>&1 ” mean?
  5. How can I profile C++ code running in Linux?

  6. What do 'real', 'user' and 'sys' mean in the output of time(1)?
  7. How do I grep recursively?
  8. Why should text files end with a newline?
  9. npm throws error without sudo
  10. Looping through the content of a file in Bash
  11. Loop through an array of strings in Bash?
  12. Difference between sh and bash
  13. How to download a file from server using SSH?
  14. What are the dark corners of Vim your mom never told you about?
  15. How do I list all cron jobs for all users?
  16. I never really understood: what is POSIX?
  17. Use grep --exclude/--include syntax to not grep through certain files
  18. What is the difference between a symbolic link and a hard link?
  19. grep, but only certain file extensions
  20. How do I remove the passphrase for the SSH key without having to create a new key?
  21. Using ls to list directories and their total sizes
  22. How can I convert a Unix timestamp to DateTime and vice versa?
  23. How to permanently set $PATH on Linux/Unix?
  24. Given two directory trees, how can I find out which files differ?
  25. How to display line numbers in less (GNU)?
  26. How to get full path of a file?
  27. Socket options SO_REUSEADDR and SO_REUSEPORT, how do they differ? Do they mean the same across all major operating systems?
  28. sed command find and replace in file and overwrite file doesn't work, it empties the file
  29. How can I reverse the order of lines in a file?
  30. How to run a shell script on a Unix console or Mac terminal?
  31. How to determine the current shell I'm working on?
  32. How to do a logical OR operation in Shell Scripting
  33. What's a concise way to check that environment variables are set in a Unix shell script?
  34. How do I write stderr to a file while using “tee” with a pipe?
  35. How do I pause my shell script for a second before continuing?
  36. How can I extract a predetermined range of lines from a text file on Unix?
  37. Why is 1/1/1970 the “epoch time”?
  38. How can I exclude directories from grep -R?
  39. What does ^M character mean in Vim?
  40. What does the number in parentheses shown after Unix command names in manpages mean?
  41. Argument list too long error for rm, cp, mv commands
  42. Bash tool to get nth line from a file
  43. How to assign name for a screen?
  44. Is PowerShell ready to replace my Cygwin shell on Windows?
  45. How to pretty print XML from the command line?
  46. How do I get cURL to not show the progress bar?
  47. OS X: equivalent of Linux's wget
  48. Unix shell script find out which directory the script file resides?
  49. Using getopts in bash shell script to get long and short command line options
  50. How to kill a process running on particular port in Linux?