LXR toybox/toys/posix/nice.c

   1/* nice.c - Run a program at a different niceness level.
   2 *
   3 * Copyright 2010 Rob Landley <rob@landley.net>
   4 *
   5 * See http://opengroup.org/onlinepubs/9699919799/utilities/nice.html
   6
   7USE_NICE(NEWTOY(nice, "^<1n#", TOYFLAG_BIN))
   8
   9config NICE
  10  bool "nice"
  11  default y
  12  help
  13    usage: nice [-n PRIORITY] COMMAND...
  14
  15    Run a command line at an increased or decreased scheduling priority.
  16
  17    Higher numbers make a program yield more CPU time, from -20 (highest
  18    priority) to 19 (lowest).  By default processes inherit their parent's
  19    niceness (usually 0).  By default this command adds 10 to the parent's
  20    priority.  Only root can set a negative niceness level.
  21*/
  22
  23#define FOR_nice
  24#include "toys.h"
  25
  26GLOBALS(
  27  long n;
  28)
  29
  30void nice_main(void)
  31{
  32  if (!toys.optflags) TT.n = 10;
  33
  34  errno = 0;
  35  if (nice(TT.n)==-1 && errno) {
  36    toys.exitval = 125;
  37    perror_exit("Can't set priority");
  38  }
  39  xexec(toys.optargs);
  40}
  41