How does testing if a string is ‘greater’ than another work in Bash?

by

From help test:

  STRING1 > STRING2
                 True if STRING1 sorts after STRING2 lexicographically.

Internally, bash either uses strcoll() or strcmp() for that:

else if ((op[0] == '>' || op[0] == '<') && op[1] == '\0')
  {
    if (shell_compatibility_level > 40 && flags & TEST_LOCALE)
      return ((op[0] == '>') ? (strcoll (arg1, arg2) > 0) : (strcoll (arg1, arg2) < 0));
    else
      return ((op[0] == '>') ? (strcmp (arg1, arg2) > 0) : (strcmp (arg1, arg2) < 0));
  }

The latter actually compares ASCII codes, the former (used when locale is enabled) performs a more specific comparison which is suitable for sorting in given locale.

More Related Contents:

  1. A variable modified inside a while loop is not remembered
  2. Can I export a variable to the environment from a Bash script without sourcing it?
  3. Passing arguments to an interactive program non-interactively
  4. Passing parameters to a Bash function
  5. How to urlencode data for curl command?
  6. How to define hash tables in Bash?
  7. Assigning default values to shell variables with a single command in bash
  8. How to zero pad a sequence of integers in bash so that all have the same width?
  9. Why isn’t tilde (~) expanding inside double quotes? [duplicate]
  10. sed search and replace strings containing / [duplicate]
  11. What is the difference between “$@” and “$*” in Bash? [duplicate]
  12. Count occurrences of a char in a string using Bash
  13. How to redirect output of an entire shell script within the script itself?
  14. Getting “command not found” error in bash script
  15. What is the exact meaning of IFS=$’\n’?
  16. How to check if running in Cygwin, Mac or Linux?
  17. VSCode Change Default Terminal
  18. Using getopts inside a Bash function
  19. choosing between $0 and BASH_SOURCE
  20. What does ${ARGUMENT+x} mean in Bash? [duplicate]
  21. How can I calculate time elapsed in a Bash script?
  22. Why does “local” discard the return code of a command?
  23. How to give a pattern for new line in grep?
  24. What does “<
  25. Comparing PHP version numbers using Bash?
  26. build argument lists containing whitespace
  27. Returning a boolean from a Bash function
  28. How do I find the number of arguments passed to a Bash script?
  29. Parallel wget in Bash [duplicate]
  30. What is more portable? echo -e or using printf?

Leave a Comment