logo

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

renice.1p (9358B)


  1. '\" et
  2. .TH RENICE "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. renice
  12. \(em set nice values of running processes
  13. .SH SYNOPSIS
  14. .LP
  15. .nf
  16. renice \fB[\fR-g|-p|-u\fB] \fR-n \fIincrement ID\fR...
  17. .fi
  18. .SH DESCRIPTION
  19. The
  20. .IR renice
  21. utility shall request that the nice values (see the Base Definitions volume of POSIX.1\(hy2017,
  22. .IR "Section 3.244" ", " "Nice Value")
  23. of one or more running processes be changed. By default, the applicable
  24. processes are specified by their process IDs. When a process group is
  25. specified (see
  26. .BR \-g ),
  27. the request shall apply to all processes in the process group.
  28. .P
  29. The nice value shall be bounded in an implementation-defined manner.
  30. If the requested
  31. .IR increment
  32. would raise or lower the nice value of the executed utility beyond
  33. implementation-defined limits, then the limit whose value was
  34. exceeded shall be used.
  35. .P
  36. When a user is
  37. .IR renice d,
  38. the request applies to all processes whose saved set-user-ID matches
  39. the user ID corresponding to the user.
  40. .P
  41. Regardless of which options are supplied or any other factor,
  42. .IR renice
  43. shall not alter the nice values of any process unless the user
  44. requesting such a change has appropriate privileges to do so for the
  45. specified process. If the user lacks appropriate privileges to perform
  46. the requested action, the utility shall return an error status.
  47. .P
  48. The saved set-user-ID of the user's process shall be checked instead of
  49. its effective user ID when
  50. .IR renice
  51. attempts to determine the user ID of the process in order to determine
  52. whether the user has appropriate privileges.
  53. .SH OPTIONS
  54. The
  55. .IR renice
  56. utility shall conform to the Base Definitions volume of POSIX.1\(hy2017,
  57. .IR "Section 12.2" ", " "Utility Syntax Guidelines",
  58. except for Guideline 9.
  59. .P
  60. The following options shall be supported:
  61. .IP "\fB\-g\fP" 10
  62. Interpret the following operands as unsigned decimal integer process
  63. group IDs.
  64. .IP "\fB\-n\ \fIincrement\fR" 10
  65. Specify how the nice value of the specified process or processes is to
  66. be adjusted. The
  67. .IR increment
  68. option-argument is a positive or negative decimal integer that shall be
  69. used to modify the nice value of the specified process or processes.
  70. .RS 10
  71. .P
  72. Positive
  73. .IR increment
  74. values shall cause a lower nice value. Negative
  75. .IR increment
  76. values may require appropriate privileges and shall cause a higher
  77. nice value.
  78. .RE
  79. .IP "\fB\-p\fP" 10
  80. Interpret the following operands as unsigned decimal integer process
  81. IDs. The
  82. .BR \-p
  83. option is the default if no options are specified.
  84. .IP "\fB\-u\fP" 10
  85. Interpret the following operands as users. If a user exists with a user
  86. name equal to the operand, then the user ID of that user is used in
  87. further processing. Otherwise, if the operand represents an unsigned
  88. decimal integer, it shall be used as the numeric user ID of the user.
  89. .SH OPERANDS
  90. The following operands shall be supported:
  91. .IP "\fIID\fR" 10
  92. A process ID, process group ID, or user name/user ID, depending on the
  93. option selected.
  94. .SH STDIN
  95. Not used.
  96. .SH "INPUT FILES"
  97. None.
  98. .SH "ENVIRONMENT VARIABLES"
  99. The following environment variables shall affect the execution of
  100. .IR renice :
  101. .IP "\fILANG\fP" 10
  102. Provide a default value for the internationalization variables that are
  103. unset or null. (See the Base Definitions volume of POSIX.1\(hy2017,
  104. .IR "Section 8.2" ", " "Internationalization Variables"
  105. for the precedence of internationalization variables used to determine
  106. the values of locale categories.)
  107. .IP "\fILC_ALL\fP" 10
  108. If set to a non-empty string value, override the values of all the
  109. other internationalization variables.
  110. .IP "\fILC_CTYPE\fP" 10
  111. Determine the locale for the interpretation of sequences of bytes of
  112. text data as characters (for example, single-byte as opposed to
  113. multi-byte characters in arguments).
  114. .IP "\fILC_MESSAGES\fP" 10
  115. .br
  116. Determine the locale that should be used to affect the format and
  117. contents of diagnostic messages written to standard error.
  118. .IP "\fINLSPATH\fP" 10
  119. Determine the location of message catalogs for the processing of
  120. .IR LC_MESSAGES .
  121. .SH "ASYNCHRONOUS EVENTS"
  122. Default.
  123. .SH STDOUT
  124. Not used.
  125. .SH STDERR
  126. The standard error shall be used only for diagnostic messages.
  127. .SH "OUTPUT FILES"
  128. None.
  129. .SH "EXTENDED DESCRIPTION"
  130. None.
  131. .SH "EXIT STATUS"
  132. The following exit values shall be returned:
  133. .IP "\00" 6
  134. Successful completion.
  135. .IP >0 6
  136. An error occurred.
  137. .SH "CONSEQUENCES OF ERRORS"
  138. Default.
  139. .LP
  140. .IR "The following sections are informative."
  141. .SH "APPLICATION USAGE"
  142. None.
  143. .SH EXAMPLES
  144. .IP " 1." 4
  145. Adjust the nice value so that process IDs 987 and 32 would have a lower
  146. nice value:
  147. .RS 4
  148. .sp
  149. .RS 4
  150. .nf
  151. renice -n 5 -p 987 32
  152. .fi
  153. .P
  154. .RE
  155. .RE
  156. .IP " 2." 4
  157. Adjust the nice value so that group IDs 324 and 76 would have a higher
  158. nice value, if the user has appropriate privileges to do so:
  159. .RS 4
  160. .sp
  161. .RS 4
  162. .nf
  163. renice -n -4 -g 324 76
  164. .fi
  165. .P
  166. .RE
  167. .RE
  168. .IP " 3." 4
  169. Adjust the nice value so that numeric user ID 8 and user
  170. .BR sas
  171. would have a lower nice value:
  172. .RS 4
  173. .sp
  174. .RS 4
  175. .nf
  176. renice -n 4 -u 8 sas
  177. .fi
  178. .P
  179. .RE
  180. .RE
  181. .P
  182. Useful nice value increments on historical systems include 19 or 20
  183. (the affected processes run only when nothing else in the system
  184. attempts to run) and any negative number (to make processes run
  185. faster).
  186. .SH RATIONALE
  187. The
  188. .IR gid ,
  189. .IR pid ,
  190. and
  191. .IR user
  192. specifications do not fit either the definition of operand or
  193. option-argument. However, for clarity, they have been included in the
  194. OPTIONS section, rather than the OPERANDS section.
  195. .P
  196. The definition of nice value is not intended to suggest that all
  197. processes in a system have priorities that are comparable. Scheduling
  198. policy extensions such as the realtime priorities in the System Interfaces volume of POSIX.1\(hy2017 make the
  199. notion of a single underlying priority for all scheduling policies
  200. problematic. Some implementations may implement the
  201. .IR nice -related
  202. features to affect all processes on the system, others to affect just
  203. the general time-sharing activities implied by this volume of POSIX.1\(hy2017, and others may
  204. have no effect at all. Because of the use of
  205. ``implementation-defined'' in
  206. .IR nice
  207. and
  208. .IR renice ,
  209. a wide range of implementation strategies are possible.
  210. .P
  211. Originally, this utility was written in the historical manner, using
  212. the term ``nice value''. This was always a point of concern with users
  213. because it was never intuitively obvious what this meant. With a newer
  214. version of
  215. .IR renice ,
  216. which used the term ``system scheduling priority'', it was hoped that
  217. novice users could better understand what this utility was meant to
  218. do. Also, it would be easier to document what the utility was meant to
  219. do. Unfortunately, the addition of the POSIX realtime scheduling
  220. capabilities introduced the concepts of process and thread scheduling
  221. priorities that were totally unaffected by the
  222. .IR nice /\c
  223. .IR renice
  224. utilities or the
  225. \fInice\fR()/\c
  226. \fIsetpriority\fR()
  227. functions. Continuing to use the term ``system scheduling priority''
  228. would have incorrectly suggested that these utilities and functions
  229. were indeed affecting these realtime priorities. It was decided to
  230. revert to the historical term ``nice value'' to reference this
  231. unrelated process attribute.
  232. .P
  233. Although this utility has use by system administrators (and in fact
  234. appears in the system administration portion of the BSD documentation),
  235. the standard developers considered that it was very useful for
  236. individual end users to control their own processes.
  237. .P
  238. Earlier versions of this standard allowed the following forms in the
  239. SYNOPSIS:
  240. .sp
  241. .RS 4
  242. .nf
  243. renice \fInice_value\fB[\fR-p\fB] \fIpid\fR...\fB[\fR-g \fIgid\fR...\fB][\fR-p \fIpid\fR...\fB][\fR-u \fIuser\fR...\fB]\fR
  244. renice \fInice_value -g \fIgid\fR...\fB[\fR-g \fIgid\fR...\fB]\fR-p \fIpid\fR...\fB][\fR-u \fIuser\fR...\fB]\fR
  245. renice \fInice_value -u \fIuser\fR...\fB[\fR-g \fIgid\fR...\fB]\fR-p \fIpid\fR...\fB][\fR-u \fIuser\fR...\fB]\fR
  246. .fi
  247. .P
  248. .RE
  249. .P
  250. These forms are no longer specified by POSIX.1\(hy2008 but may be
  251. present in some implementations.
  252. .SH "FUTURE DIRECTIONS"
  253. None.
  254. .SH "SEE ALSO"
  255. .IR "\fInice\fR\^"
  256. .P
  257. The Base Definitions volume of POSIX.1\(hy2017,
  258. .IR "Section 3.244" ", " "Nice Value",
  259. .IR "Chapter 8" ", " "Environment Variables",
  260. .IR "Section 12.2" ", " "Utility Syntax Guidelines"
  261. .\"
  262. .SH COPYRIGHT
  263. Portions of this text are reprinted and reproduced in electronic form
  264. from IEEE Std 1003.1-2017, Standard for Information Technology
  265. -- Portable Operating System Interface (POSIX), The Open Group Base
  266. Specifications Issue 7, 2018 Edition,
  267. Copyright (C) 2018 by the Institute of
  268. Electrical and Electronics Engineers, Inc and The Open Group.
  269. In the event of any discrepancy between this version and the original IEEE and
  270. The Open Group Standard, the original IEEE and The Open Group Standard
  271. is the referee document. The original Standard can be obtained online at
  272. http://www.opengroup.org/unix/online.html .
  273. .PP
  274. Any typographical or formatting errors that appear
  275. in this page are most likely
  276. to have been introduced during the conversion of the source files to
  277. man page format. To report such errors, see
  278. https://www.kernel.org/doc/man-pages/reporting_bugs.html .