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diff --git a/upstream/mageia-cauldron/man1p/head.1p b/upstream/mageia-cauldron/man1p/head.1p new file mode 100644 index 00000000..0d9f6637 --- /dev/null +++ b/upstream/mageia-cauldron/man1p/head.1p @@ -0,0 +1,216 @@ +'\" et +.TH HEAD "1P" 2017 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" +.SH PROLOG +This manual page is part of the POSIX Programmer's Manual. +The Linux implementation of this interface may differ (consult +the corresponding Linux manual page for details of Linux behavior), +or the interface may not be implemented on Linux. +.\" +.SH NAME +head +\(em copy the first part of files +.SH SYNOPSIS +.LP +.nf +head \fB[\fR-n \fInumber\fB] [\fIfile\fR...\fB]\fR +.fi +.SH DESCRIPTION +The +.IR head +utility shall copy its input files to the standard output, ending the +output for each file at a designated point. +.P +Copying shall end at the point in each input file indicated by the +.BR \-n +.IR number +option. The option-argument +.IR number +shall be counted in units of lines. +.SH OPTIONS +The +.IR head +utility shall conform to the Base Definitions volume of POSIX.1\(hy2017, +.IR "Section 12.2" ", " "Utility Syntax Guidelines". +.P +The following option shall be supported: +.IP "\fB\-n\ \fInumber\fR" 10 +The first +.IR number +lines of each input file shall be copied to standard output. The +application shall ensure that the +.IR number +option-argument is a positive decimal integer. +.P +When a file contains less than +.IR number +lines, it shall be copied to standard output in its entirety. This +shall not be an error. +.P +If no options are specified, +.IR head +shall act as if +.BR "\-n 10" +had been specified. +.SH OPERANDS +The following operand shall be supported: +.IP "\fIfile\fR" 10 +A pathname of an input file. If no +.IR file +operands are specified, the standard input shall be used. +.SH STDIN +The standard input shall be used if no +.IR file +operands are specified, and shall be used if a +.IR file +operand is +.BR '\-' +and the implementation treats the +.BR '\-' +as meaning standard input. +Otherwise, the standard input shall not be used. +See the INPUT FILES section. +.SH "INPUT FILES" +Input files shall be text files, but the line length is not restricted +to +{LINE_MAX} +bytes. +.SH "ENVIRONMENT VARIABLES" +The following environment variables shall affect the execution of +.IR head : +.IP "\fILANG\fP" 10 +Provide a default value for the internationalization variables that are +unset or null. (See the Base Definitions volume of POSIX.1\(hy2017, +.IR "Section 8.2" ", " "Internationalization Variables" +for the precedence of internationalization variables used to determine +the values of locale categories.) +.IP "\fILC_ALL\fP" 10 +If set to a non-empty string value, override the values of all the +other internationalization variables. +.IP "\fILC_CTYPE\fP" 10 +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 and input files). +.IP "\fILC_MESSAGES\fP" 10 +.br +Determine the locale that should be used to affect the format and +contents of diagnostic messages written to standard error. +.IP "\fINLSPATH\fP" 10 +Determine the location of message catalogs for the processing of +.IR LC_MESSAGES . +.SH "ASYNCHRONOUS EVENTS" +Default. +.SH STDOUT +The standard output shall contain designated portions of the input +files. +.P +If multiple +.IR file +operands are specified, +.IR head +shall precede the output for each with the header: +.sp +.RS 4 +.nf + +"\en==> %s <==\en", <\fIpathname\fR> +.fi +.P +.RE +.P +except that the first header written shall not include the initial +<newline>. +.SH STDERR +The standard error shall be used only for diagnostic messages. +.SH "OUTPUT FILES" +None. +.SH "EXTENDED DESCRIPTION" +None. +.SH "EXIT STATUS" +The following exit values shall be returned: +.IP "\00" 6 +Successful completion. +.IP >0 6 +An error occurred. +.SH "CONSEQUENCES OF ERRORS" +Default. +.LP +.IR "The following sections are informative." +.SH "APPLICATION USAGE" +When using +.IR head +to process pathnames, it is recommended that LC_ALL, or at least +LC_CTYPE and LC_COLLATE, are set to POSIX or C in the environment, +since pathnames can contain byte sequences that do not form valid +characters in some locales, in which case the utility's behavior would +be undefined. In the POSIX locale each byte is a valid single-byte +character, and therefore this problem is avoided. +.SH EXAMPLES +To write the first ten lines of all files (except those with a leading +period) in the directory: +.sp +.RS 4 +.nf + +head -- * +.fi +.P +.RE +.SH RATIONALE +Although it is possible to simulate +.IR head +with +.IR sed +10q for a single file, the standard developers decided that the +popularity of +.IR head +on historical BSD systems warranted its inclusion alongside +.IR tail . +.P +POSIX.1\(hy2008 version of +.IR head +follows the Utility Syntax Guidelines. The +.BR \-n +option was added to this new interface so that +.IR head +and +.IR tail +would be more logically related. Earlier versions of this standard +allowed a +.BR \-number +option. This form is no longer specified by POSIX.1\(hy2008 but may +be present in some implementations. +.P +There is no +.BR \-c +option (as there is in +.IR tail ) +because it is not historical practice and because other utilities in +\&this volume of POSIX.1\(hy2017 provide similar functionality. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIsed\fR\^", +.IR "\fItail\fR\^" +.P +The Base Definitions volume of POSIX.1\(hy2017, +.IR "Chapter 8" ", " "Environment Variables", +.IR "Section 12.2" ", " "Utility Syntax Guidelines" +.\" +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1-2017, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, 2018 Edition, +Copyright (C) 2018 by the Institute 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.opengroup.org/unix/online.html . +.PP +Any typographical or formatting errors that appear +in this page are most likely +to have been introduced during the conversion of the source files to +man page format. To report such errors, see +https://www.kernel.org/doc/man-pages/reporting_bugs.html . |