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oasis-root

Compiled tree of Oasis Linux based on own branch at <https://hacktivis.me/git/oasis/> git clone https://anongit.hacktivis.me/git/oasis-root.git

colon.1p (2489B)

    

  1. '\" et
  2. .TH COLON "1P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual"
  3. .\"
  4. .SH PROLOG
  5. This manual page is part of the POSIX Programmer's Manual.
  6. The Linux implementation of this interface may differ (consult
  7. the corresponding Linux manual page for details of Linux behavior),
  8. or the interface may not be implemented on Linux.
  9. .\"
  10. .SH NAME
  11. colon
  12. \(em null utility
  13. .SH SYNOPSIS
  14. .LP
  15. .nf
  16. : \fB[\fIargument\fR...\fB]\fR
  17. .fi
  18. .SH DESCRIPTION
  19. This utility shall only expand command
  20. .IR argument s.
  21. It is used when a command is needed, as in the
  22. .BR then
  23. condition of an
  24. .BR if
  25. command, but nothing is to be done by the command.
  26. .SH OPTIONS
  27. None.
  28. .SH OPERANDS
  29. See the DESCRIPTION.
  30. .SH STDIN
  31. Not used.
  32. .SH "INPUT FILES"
  33. None.
  34. .SH "ENVIRONMENT VARIABLES"
  35. None.
  36. .SH "ASYNCHRONOUS EVENTS"
  37. Default.
  38. .SH STDOUT
  39. Not used.
  40. .SH STDERR
  41. The standard error shall be used only for diagnostic messages.
  42. .SH "OUTPUT FILES"
  43. None.
  44. .SH "EXTENDED DESCRIPTION"
  45. None.
  46. .SH "EXIT STATUS"
  47. Zero.
  48. .SH "CONSEQUENCES OF ERRORS"
  49. Default.
  50. .LP
  51. .IR "The following sections are informative."
  52. .SH "APPLICATION USAGE"
  53. None.
  54. .SH EXAMPLES
  55. .LP
  56. .nf
  57. : ${X=abc}
  58. if     false
  59. then   :
  60. else   echo $X
  61. fi
  62. \fBabc\fR
  63. .fi
  64. .P
  65. As with any of the special built-ins, the null utility can also have
  66. variable assignments and redirections associated with it, such as:
  67. .sp
  68. .RS 4
  69. .nf
  71. x=y : > z
  72. .fi
  73. .P
  74. .RE
  75. .P
  76. which sets variable
  77. .IR x
  78. to the value
  79. .IR y
  80. (so that it persists after the null utility completes) and creates or
  81. truncates file
  82. .BR z .
  83. .SH "RATIONALE"
  84. None.
  85. .SH "FUTURE DIRECTIONS"
  86. None.
  87. .SH "SEE ALSO"
  88. .IR "Section 2.14" ", " "Special Built-In Utilities"
  89. .\"
  90. .SH COPYRIGHT
  91. Portions of this text are reprinted and reproduced in electronic form
  92. from IEEE Std 1003.1-2017, Standard for Information Technology
  93. -- Portable Operating System Interface (POSIX), The Open Group Base
  94. Specifications Issue 7, 2018 Edition,
  95. Copyright (C) 2018 by the Institute of
  96. Electrical and Electronics Engineers, Inc and The Open Group.
  97. In the event of any discrepancy between this version and the original IEEE and
  98. The Open Group Standard, the original IEEE and The Open Group Standard
  99. is the referee document. The original Standard can be obtained online at
  100. http://www.opengroup.org/unix/online.html .
  101. .PP
  102. Any typographical or formatting errors that appear
  103. in this page are most likely
  104. to have been introduced during the conversion of the source files to
  105. man page format. To report such errors, see
  106. https://www.kernel.org/doc/man-pages/reporting_bugs.html .