What does “-ne” mean in bash?

This is one of those things that can be difficult to search for if you don’t already know where to look.

[ is actually a command, not part of the bash shell syntax as you might expect. It happens to be a Bash built-in command, so it’s documented in the Bash manual.

There’s also an external command that does the same thing; on many systems, it’s provided by the GNU Coreutils package.

[ is equivalent to the test command, except that [ requires ] as its last argument, and test does not.

Assuming the bash documentation is installed on your system, if you type info bash and search for 'test' or '[' (the apostrophes are part of the search), you’ll find the documentation for the [ command, also known as the test command. If you use man bash instead of info bash, search for ^ *test (the word test at the beginning of a line, following some number of spaces).

Following the reference to “Bash Conditional Expressions” will lead you to the description of -ne, which is the numeric inequality operator (“ne” stands for “not equal). By contrast, != is the string inequality operator.

You can also find bash documentation on the web.

The official definition of the test command is the POSIX standard (to which the bash implementation should conform reasonably well, perhaps with some extensions).

Related Posts:

  1. How to concatenate string variables in Bash
  2. How do I iterate over a range of numbers defined by variables in Bash?
  3. How do I iterate over a range of numbers defined by variables in Bash?
  4. How do I split a string on a delimiter in Bash?
  5. Ubuntu says “bash: ./program Permission denied” [closed]
  6. -bash: syntax error near unexpected token `)’
  7. An example of how to use getopts in bash
  8. “unary operator expected” error in Bash if condition
  9. What is the purpose of “&&” in a shell command?
  10. How to generate random number in Bash?
  11. How to check if a variable is set in Bash?
  12. How can I compare numbers in Bash?
  13. Open and write data to text file using Bash?
  14. How do I set a variable to the output of a command in Bash?
  15. Is there a TRY CATCH command in Bash
  16. Run a string as a command within a Bash script
  17. Meaning of “! -S” in shell script
  18. “No such file or directory” but it exists
  19. How do I pause my shell script for a second before continuing?
  20. In the shell, what does ” 2>&1 ” mean?
  21. Is double square brackets [[ ]] preferable over single square brackets [ ] in Bash?
  22. Extract substring in Bash
  23. Should I put #! (shebang) in Python scripts, and what form should it take?
  24. Should I put #! (shebang) in Python scripts, and what form should it take?
  25. In the shell, what does ” 2>&1 ” mean?
  26. How do I use a regex in a shell script?
  27. How do I copy a folder from remote to local using scp?
  28. How to grep for case insensitive string in a file?
  29. Difference between wait and sleep
  30. Multi-line string with extra space (preserved indentation)
  31. How to delete from a text file, all lines that contain a specific string?
  32. Multi-line string with extra space (preserved indentation)
  33. How to mkdir only if a directory does not already exist?
  34. -bash: syntax error near unexpected token `newline’
  35. Loop through an array of strings in Bash?
  36. ‘\r’: command not found – .bashrc / .bash_profile [duplicate]
  37. How to set ssh timeout?
  38. commands not found on zsh
  39. sudo: apt-get: command not found
  40. How to mkdir only if a directory does not already exist?
  41. -bash: syntax error near unexpected token `newline’ for display command
  42. Using find to locate files that match one of multiple patterns
  43. “sed” command in bash
  44. How can I declare and use Boolean variables in a shell script?
  45. How to reload .bashrc settings without logging out and back in again?
  46. Is there a Python equivalent to the ‘which’ command
  47. How can I declare and use Boolean variables in a shell script?
  48. How to reload .bash_profile from the command line?
  49. Replace one substring for another string in shell script
  50. “[ ]” vs. “[[ ]]” in Bash shell
  51. How do I split a string on a delimiter in Bash?
  52. Pseudo-terminal will not be allocated because stdin is not a terminal
  53. Who can access a file with octal permissions “000” on Linux/UNIX?
  54. What is a list in Bash?
  55. What does the line “#!/bin/sh” mean in a UNIX shell script?
  56. How can I count all the lines of code in a directory recursively?
  57. How can I kill a process by name instead of PID, on Linux?
  58. Given two directory trees, how can I find out which files differ by content?
  59. How to remove the quotes when reading a variable in jq in shell?
  60. Shell script “for” loop syntax
  61. Shell: How to call one shell script from another shell script?
  62. Ternary operator (?:) in Bash
  63. Pseudo-terminal will not be allocated because stdin is not a terminal
  64. find: missing argument to -exec
  65. How to escape single quotes within single quoted strings
  66. python getoutput() equivalent in subprocess
  67. ./configure : /bin/sh^M : bad interpreter
  68. What is the $? (dollar question mark) variable in shell scripting?
  69. How to check if an environment variable exists and get its value?
  70. What is the difference between “#!/usr/bin/env bash” and “#!/usr/bin/bash”?
  71. Bash syntax error: unexpected end of file
  72. Bash syntax error: unexpected end of file
  73. How to convert a string to lower case in Bash?
  74. Is there a “goto” statement in bash?
  75. dquote> result of a execution a program in linux shell
  76. Using sudo with Python script
  77. how to fix the issue “Command /bin/sh failed with exit code 1” in iphone
  78. Create a new file in git bash
  79. Sorting data based on second column of a file
  80. chmod: changing permissions of ‘my_script.sh’: Operation not permitted
  81. zip error – Nothing to do
  82. How to sort an array in Bash
  83. Associative arrays in Shell scripts
  84. How to split one string into multiple strings separated by at least one space in bash shell?
  85. Copy multiple files from one directory to another from Linux shell
  86. Shell script not running, command not found
  87. How to get a shell environment variable in a makefile?
  88. Difference between sh and Bash
  89. What are the uses of the exec command in shell scripts? 
  90. using rot13 and tr command for having an encrypted email address
  91. Shell Script: Execute a python program from within a shell script
  92. sed whole word search and replace
  93. Integer expression expected error in shell script
  94. What is the difference between double and single square brackets in bash?
  95. What is “-bash: !”: event not found”
  96. How to add a timestamp to bash script log?
  97. Colors in bash after piping through less?
  98. What’s the difference betwen the single dash and double dash flags on shell commands?
  99. How to run command as user who has /usr/sbin/nologin as Shell?
  100. How to let ‘cp’ command don’t fire an error when source file does not exist?

Leave a Comment