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diff --git a/coreutils-5.3.0-bin/man/cat1p/env.1p.txt b/coreutils-5.3.0-bin/man/cat1p/env.1p.txt new file mode 100644 index 0000000..119f6c4 --- /dev/null +++ b/coreutils-5.3.0-bin/man/cat1p/env.1p.txt @@ -0,0 +1,233 @@ +env(P) env(P) + + + + + +NAME + env - set the environment for command invocation + +SYNOPSIS + env [-i][name=value]... [utility [argument...]] + +DESCRIPTION + The env utility shall obtain the current environment, + modify it according to its arguments, then invoke the + utility named by the utility operand with the modified + environment. + + Optional arguments shall be passed to utility. + + If no utility operand is specified, the resulting envi- + ronment shall be written to the standard output, with + one name= value pair per line. + +OPTIONS + The env utility shall conform to the Base Definitions + volume of IEEE Std 1003.1-2001, Section 12.2, Utility + Syntax Guidelines. + + The following options shall be supported: + + -i Invoke utility with exactly the environment spec- + ified by the arguments; the inherited environment + shall be ignored completely. + + +OPERANDS + The following operands shall be supported: + + name=value + Arguments of the form name= value shall modify + the execution environment, and shall be placed + into the inherited environment before the utility + is invoked. + + utility + The name of the utility 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 + A string to pass as an argument for the invoked + utility. + + +STDIN + Not used. + +INPUT FILES + None. + +ENVIRONMENT VARIABLES + The following environment variables shall affect the + execution of env: + + 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 location of the utility, as + described in the Base Definitions volume of + IEEE Std 1003.1-2001, Chapter 8, Environment + Variables. If PATH is specified as a name= value + operand to env, the value given shall be used in + the search for utility. + + +ASYNCHRONOUS EVENTS + Default. + +STDOUT + If no utility operand is specified, each name= value + pair in the resulting environment shall be written in + the form: + + + "%s=%s\n", <name>, <value> + + If the utility operand is specified, the env utility + shall not write to standard output. + +STDERR + The standard error shall be used only for diagnostic + messages. + +OUTPUT FILES + None. + +EXTENDED DESCRIPTION + None. + +EXIT STATUS + If utility is invoked, the exit status of env shall be + the exit status of utility; otherwise, the env utility + shall exit with one of the following values: + + 0 The env utility completed successfully. + + 1-125 An error occurred in the env utility. + + 126 The utility specified by utility was found but + could not be invoked. + + 127 The utility specified by utility could not be + found. + + +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. + + Historical implementations of the env utility use the + execvp() or execlp() functions defined in the System + Interfaces volume of IEEE Std 1003.1-2001 to invoke the + specified utility; this provides better performance and + keeps users from having to escape characters with spe- + cial meaning to the shell. Therefore, shell functions, + special built-ins, and built-ins that are only provided + by the shell are not found. + +EXAMPLES + The following command: + + + env -i PATH=/mybin mygrep xyz myfile + + invokes the command mygrep with a new PATH value as the + only entry in its environment. In this case, PATH is + used to locate mygrep, which then must reside in /mybin. + +RATIONALE + As with all other utilities that invoke other utilities, + this volume of IEEE Std 1003.1-2001 only specifies what + env does with standard input, standard output, standard + error, input files, and output files. If a utility is + executed, it is not constrained by the specification of + input and output by env. + + The -i option was added to allow the functionality of + the withdrawn - option in a manner compatible with the + Utility Syntax Guidelines. + + Some have suggested that env is redundant since the same + effect is achieved by: + + + name=value ... utility [ argument ... ] + + The example is equivalent to env when an environment + variable is being added to the environment of the com- + mand, but not when the environment is being set to the + given value. The env utility also writes out the current + environment if invoked without arguments. There is suf- + ficient functionality beyond what the example provides + to justify inclusion of env. + +FUTURE DIRECTIONS + None. + +SEE ALSO + Parameters and Variables , Special Built-In Utilities + +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 env(P) |