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diff --git a/coreutils-5.3.0-bin/man/cat1p/nohup.1p.txt b/coreutils-5.3.0-bin/man/cat1p/nohup.1p.txt new file mode 100644 index 0000000..10d1fd2 --- /dev/null +++ b/coreutils-5.3.0-bin/man/cat1p/nohup.1p.txt @@ -0,0 +1,229 @@ +nohup(P) nohup(P) + + + + + +NAME + nohup - invoke a utility immune to hangups + +SYNOPSIS + nohup utility [argument...] + +DESCRIPTION + The nohup utility shall invoke the utility named by the + utility operand with arguments supplied as the argument + operands. At the time the named utility is invoked, the + SIGHUP signal shall be set to be ignored. + + If the standard output is a terminal, all output written + by the named utility to its standard output shall be + appended to the end of the file nohup.out in the current + directory. If nohup.out cannot be created or opened for + appending, the output shall be appended to the end of + the file nohup.out in the directory specified by the + HOME environment variable. If neither file can be cre- + ated or opened for appending, utility shall not be + invoked. If a file is created, the file's permission + bits shall be set to S_IRUSR | S_IWUSR. + + If the standard error is a terminal, all output written + by the named utility to its standard error shall be + redirected to the same file descriptor as the standard + output. + +OPTIONS + None. + +OPERANDS + The following operands shall be supported: + + utility + The name of a utility that is to be invoked. If + the utility operand names any of the special + built-in utilities in Special Built-In Utilities + , the results are undefined. + + argument + Any string to be supplied as an argument when + invoking the utility named by the utility oper- + and. + + +STDIN + Not used. + +INPUT FILES + None. + +ENVIRONMENT VARIABLES + The following environment variables shall affect the + execution of nohup: + + HOME Determine the pathname of the user's home direc- + tory: if the output file nohup.out cannot be cre- + ated in the current directory, the nohup utility + shall use the directory named by HOME to create + the file. + + LANG Provide a default value for the internationaliza- + tion variables that are unset or null. (See the + Base Definitions volume of IEEE Std 1003.1-2001, + Section 8.2, Internationalization Variables for + the precedence of internationalization variables + used to determine the values of locale cate- + gories.) + + LC_ALL If set to a non-empty string value, override the + values of all the other internationalization + variables. + + LC_CTYPE + Determine the locale for the interpretation of + sequences of bytes of text data as characters + (for example, single-byte as opposed to multi- + byte characters in arguments). + + LC_MESSAGES + Determine the locale that should be used to + affect the format and contents of diagnostic mes- + sages written to standard error. + + NLSPATH + Determine the location of message catalogs for + the processing of LC_MESSAGES . + + PATH Determine the search path that is used to locate + the utility to be invoked. See the Base Defini- + tions volume of IEEE Std 1003.1-2001, Chapter 8, + Environment Variables. + + +ASYNCHRONOUS EVENTS + The nohup utility shall take the standard action for all + signals except that SIGHUP shall be ignored. + +STDOUT + If the standard output is not a terminal, the standard + output of nohup shall be the standard output generated + by the execution of the utility specified by the oper- + ands. Otherwise, nothing shall be written to the stan- + dard output. + +STDERR + If the standard output is a terminal, a message shall be + written to the standard error, indicating the name of + the file to which the output is being appended. The name + of the file shall be either nohup.out or + $HOME/nohup.out. + +OUTPUT FILES + If the standard output is a terminal, all output written + by the named utility to the standard output and standard + error is appended to the file nohup.out, which is cre- + ated if it does not already exist. + +EXTENDED DESCRIPTION + None. + +EXIT STATUS + The following exit values shall be returned: + + 126 The utility specified by utility was found but + could not be invoked. + + 127 An error occurred in the nohup utility or the + utility specified by utility could not be found. + + + Otherwise, the exit status of nohup shall be that of the + utility specified by the utility operand. + +CONSEQUENCES OF ERRORS + Default. + + The following sections are informative. + +APPLICATION USAGE + The command, env, nice, nohup, time, and xargs utilities + have been specified to use exit code 127 if an error + occurs so that applications can distinguish "failure to + find a utility" from "invoked utility exited with an + error indication". The value 127 was chosen because it + is not commonly used for other meanings; most utilities + use small values for "normal error conditions" and the + values above 128 can be confused with termination due to + receipt of a signal. The value 126 was chosen in a simi- + lar manner to indicate that the utility could be found, + but not invoked. Some scripts produce meaningful error + messages differentiating the 126 and 127 cases. The dis- + tinction between exit codes 126 and 127 is based on + KornShell practice that uses 127 when all attempts to + exec the utility fail with [ENOENT], and uses 126 when + any attempt to exec the utility fails for any other rea- + son. + +EXAMPLES + It is frequently desirable to apply nohup to pipelines + or lists of commands. This can be done by placing pipe- + lines and command lists in a single file; this file can + then be invoked as a utility, and the nohup applies to + everything in the file. + + Alternatively, the following command can be used to + apply nohup to a complex command: + + + nohup sh -c 'complex-command-line' + +RATIONALE + The 4.3 BSD version ignores SIGTERM and SIGHUP, and if + ./nohup.out cannot be used, it fails instead of trying + to use $HOME/nohup.out. + + The csh utility has a built-in version of nohup that + acts differently from the nohup defined in this volume + of IEEE Std 1003.1-2001. + + The term utility is used, rather than command, to high- + light the fact that shell compound commands, pipelines, + special built-ins, and so on, cannot be used directly. + However, utility includes user application programs and + shell scripts, not just the standard utilities. + + Historical versions of the nohup utility use default + file creation semantics. Some more recent versions use + the permissions specified here as an added security pre- + caution. + + Some historical implementations ignore SIGQUIT in addi- + tion to SIGHUP; others ignore SIGTERM. An early proposal + allowed, but did not require, SIGQUIT to be ignored. + Several reviewers objected that nohup should only modify + the handling of SIGHUP as required by this volume of + IEEE Std 1003.1-2001. + +FUTURE DIRECTIONS + None. + +SEE ALSO + Shell Command Language , sh , the System Interfaces + volume of IEEE Std 1003.1-2001, signal() + +COPYRIGHT + Portions of this text are reprinted and reproduced in + electronic form from IEEE Std 1003.1, 2003 Edition, + Standard for Information Technology -- Portable Operat- + ing System Interface (POSIX), The Open Group Base Speci- + fications Issue 6, Copyright (C) 2001-2003 by the Insti- + tute of Electrical and Electronics Engineers, Inc and + The Open Group. In the event of any discrepancy between + this version and the original IEEE and The Open Group + Standard, the original IEEE and The Open Group Standard + is the referee document. The original Standard can be + obtained online at http://www.open- + group.org/unix/online.html . + + + +POSIX 2003 nohup(P) |