Source Code 1994 March/Source_Code_CD-ROM_Walnut_Creek_March_1994.iso/compsrcs/misc/volume33/nhup/part01

Text File | 1992-11-19 | 3.9 KB | 140 lines

Newsgroups: comp.sources.misc
From: [e-mail] (Gnanasekaran  Swaminathan)
Subject:  v33i080:  nhup - another nohup program, Part01/01
Message-ID: <[e-mail]>
X-Md4-Signature: 8efdf55646b08d17a32d31cb5c6522f5
Date: Thu, 19 Nov 1992 03:20:17 GMT
Approved: [e-mail]

Submitted-by: [e-mail] (Gnanasekaran  Swaminathan)
Posting-number: Volume 33, Issue 80
Archive-name: nhup/part01
Environment: UNIX

nhup executes the command with the given arguments
in the background  and returns immediately without
waiting  for the  command to complete.  Also,  the
process executing the command is  immune to hangup
(HUP) and quit (QUIT) signals.

Unlike  nohup,  nhup does not redirect the  stdout
and  the stderr of the command to  nohup.out file.
Instead, it leaves the option to the user. If  the
user fails to specify any, the stdout and the std-
err are redirected to /dev/null.
----------
#! /bin/sh
# This is a shell archive.  Remove anything before this line, then feed it
# into a shell via "sh file" or similar.  To overwrite existing files,
# type "sh file -c".
# Contents:  Makefile nhup.c
# Wrapped by kent@sparky on Wed Nov 18 21:14:48 1992
PATH=/bin:/usr/bin:/usr/ucb:/usr/local/bin:/usr/lbin ; export PATH
echo If this archive is complete, you will see the following message:
echo '          "shar: End of archive."'
if test -f 'Makefile' -a "${1}" != "-c" ; then
  echo shar: Will not clobber existing file \"'Makefile'\"
else
  echo shar: Extracting \"'Makefile'\" \(79 characters\)
  sed "s/^X//" >'Makefile' <<'END_OF_FILE'
XCC=gcc
X
X
Xnhup: nhup.c
X    $(CC) -o nhup nhup.c
X
Xinstall: nhup
X    cp nhup /bin/nhup
END_OF_FILE
  if test 79 -ne `wc -c <'Makefile'`; then
    echo shar: \"'Makefile'\" unpacked with wrong size!
  fi
  # end of 'Makefile'
fi
if test -f 'nhup.c' -a "${1}" != "-c" ; then
  echo shar: Will not clobber existing file \"'nhup.c'\"
else
  echo shar: Extracting \"'nhup.c'\" \(1644 characters\)
  sed "s/^X//" >'nhup.c' <<'END_OF_FILE'
X/*
X    NAME
X        nhup -- run a command immune to hangups and quits.
X
X    SYNOPSIS
X        nhup command [ arguments ]
X
X    DESCRIPTION
X        nhup executes the command with the given arguments
X        in the background  and returns immediately without
X        waiting  for the  command to complete.  Also,  the
X        process executing the command is  immune to hangup
X        (HUP) and quit (QUIT) signals.
X
X        Unlike  nohup,  nhup does not redirect the  stdout
X        and  the stderr of the command to  nohup.out file.
X        Instead, it leaves the option to the user. If  the
X        user fails to specify any, the stdout and the std-
X        err are redirected to /dev/null.
X
X    EXAMPLES
X        % nhup prog1 | prog2
X        Run  prog1 and  pipe  its output to prog2  and re-
X        direct the stderr of prog1 to /dev/null.
X
X        % nhup prog1 > test 2> testerr
X        Run prog1  by directing its stdout to test and its
X        stderr to testerr.
X
X        % nhup prog1
X        Run prog1  by directing its stdout and  its stderr
X        to /dev/null
X
X    SEE ALSO
X        nohup(1), signal(3)
X
X    BUGS
X        Send them to Gnanasekaran Swaminathan <[e-mail]>
X*/
X
X#include <unistd.h>
X#include <fcntl.h>
X#include <stdio.h>
X#include <stdlib.h>
X#include <sys/signal.h>
X
Xstatic void error(const char* a1) { perror(a1); exit(1); }
X
Xint main(int ac, char** av)
X{
X    int p = fork();
X    if (p == -1)
X        error(av[0]);
X    if (p == 0) {
X        /* child process */
X        int fd = open("/dev/null", O_WRONLY);
X
X        signal(SIGHUP, SIG_IGN);
X        signal(SIGQUIT, SIG_IGN);
X
X        if ( isatty(STDOUT_FILENO) && dup2(fd, STDOUT_FILENO) == -1 )
X            error(av[0]);
X        if ( isatty(STDERR_FILENO) && dup2(fd, STDERR_FILENO) == -1 )
X            error(av[0]);
X
X        execvp(av[1], av+1);
X        error(av[1]);
X    }
X    return 0;
X}
X
X
END_OF_FILE
  if test 1644 -ne `wc -c <'nhup.c'`; then
    echo shar: \"'nhup.c'\" unpacked with wrong size!
  fi
  # end of 'nhup.c'
fi
echo shar: End of archive.
exit 0
exit 0 # Just in case...