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52 lines
1.4 KiB
C
52 lines
1.4 KiB
C
/* vi: set sw=4 ts=4: */
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/*
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* usleep implementation for busybox
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*
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* Copyright (C) 2003 Manuel Novoa III <mjn3@codepoet.org>
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*
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* Licensed under GPLv2 or later, see file LICENSE in this source tree.
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*/
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//config:config USLEEP
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//config: bool "usleep (1.3 kb)"
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//config: default y
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//config: help
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//config: usleep is used to pause for a specified number of microseconds.
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//applet:IF_USLEEP(APPLET_NOFORK(usleep, usleep, BB_DIR_BIN, BB_SUID_DROP, usleep))
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//kbuild:lib-$(CONFIG_USLEEP) += usleep.o
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/* BB_AUDIT SUSv3 N/A -- Apparently a busybox extension. */
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//usage:#define usleep_trivial_usage
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//usage: "N"
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//usage:#define usleep_full_usage "\n\n"
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//usage: "Pause for N microseconds"
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//usage:
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//usage:#define usleep_example_usage
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//usage: "$ usleep 1000000\n"
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//usage: "[pauses for 1 second]\n"
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#include "libbb.h"
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/* This is a NOFORK applet. Be very careful! */
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int usleep_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
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int usleep_main(int argc UNUSED_PARAM, char **argv)
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{
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if (!argv[1]) {
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bb_show_usage();
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}
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/* Safe wrt NOFORK? (noforks are not allowed to run for
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* a long time). Try "usleep 99999999" + ^C + "echo $?"
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* in hush with FEATURE_SH_NOFORK=y.
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* At least on uclibc, usleep() thanslates to nanosleep()
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* which returns early on any signal (even caught one),
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* and uclibc does not loop back on EINTR.
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*/
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usleep(xatou(argv[1]));
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return EXIT_SUCCESS;
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}
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