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diff --git a/man-pages-posix-2003/man1p/head.1p b/man-pages-posix-2003/man1p/head.1p new file mode 100644 index 0000000..4356b03 --- /dev/null +++ b/man-pages-posix-2003/man1p/head.1p @@ -0,0 +1,181 @@ +.\" Copyright (c) 2001-2003 The Open Group, All Rights Reserved +.TH "HEAD" 1P 2003 "IEEE/The Open Group" "POSIX Programmer's Manual" +.\" head +.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 \- copy the first part of files +.SH SYNOPSIS +.LP +\fBhead\fP \fB[\fP\fB-n\fP \fInumber\fP\fB][\fP\fIfile\fP\fB...\fP\fB]\fP +.SH DESCRIPTION +.LP +The \fIhead\fP utility shall copy its input files to the standard +output, ending the output for each file at a designated +point. +.LP +Copying shall end at the point in each input file indicated by the +\fB-n\fP \fInumber\fP option. The option-argument +\fInumber\fP shall be counted in units of lines. +.SH OPTIONS +.LP +The \fIhead\fP utility shall conform to the Base Definitions volume +of IEEE\ Std\ 1003.1-2001, Section 12.2, Utility Syntax Guidelines. +.LP +The following option shall be supported: +.TP 7 +\fB-n\ \fP \fInumber\fP +The first \fInumber\fP lines of each input file shall be copied to +standard output. The application shall ensure that the +\fInumber\fP option-argument is a positive decimal integer. +.sp +.LP +When a file contains less than \fInumber\fP lines, it shall be copied +to standard output in its entirety. This shall not be an +error. +.LP +If no options are specified, \fIhead\fP shall act as if \fB-n 10\fP +had been specified. +.SH OPERANDS +.LP +The following operand shall be supported: +.TP 7 +\fIfile\fP +A pathname of an input file. If no \fIfile\fP operands are specified, +the standard input shall be used. +.sp +.SH STDIN +.LP +The standard input shall be used only if no \fIfile\fP operands are +specified. See the INPUT FILES section. +.SH INPUT FILES +.LP +Input files shall be text files, but the line length is not restricted +to {LINE_MAX} bytes. +.SH ENVIRONMENT VARIABLES +.LP +The following environment variables shall affect the execution of +\fIhead\fP: +.TP 7 +\fILANG\fP +Provide a default value for the internationalization 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 categories.) +.TP 7 +\fILC_ALL\fP +If set to a non-empty string value, override the values of all the +other internationalization variables. +.TP 7 +\fILC_CTYPE\fP +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). +.TP 7 +\fILC_MESSAGES\fP +Determine the locale that should be used to affect the format and +contents of diagnostic messages written to standard +error. +.TP 7 +\fINLSPATH\fP +Determine the location of message catalogs for the processing of \fILC_MESSAGES +\&.\fP +.sp +.SH ASYNCHRONOUS EVENTS +.LP +Default. +.SH STDOUT +.LP +The standard output shall contain designated portions of the input +files. +.LP +If multiple \fIfile\fP operands are specified, \fIhead\fP shall precede +the output for each with the header: +.sp +.RS +.nf + +\fB"\\n==> %s <==\\n", <\fP\fIpathname\fP\fB> +\fP +.fi +.RE +.LP +except that the first header written shall not include the initial +<newline>. +.SH STDERR +.LP +The standard error shall be used only for diagnostic messages. +.SH OUTPUT FILES +.LP +None. +.SH EXTENDED DESCRIPTION +.LP +None. +.SH EXIT STATUS +.LP +The following exit values shall be returned: +.TP 7 +\ 0 +Successful completion. +.TP 7 +>0 +An error occurred. +.sp +.SH CONSEQUENCES OF ERRORS +.LP +Default. +.LP +\fIThe following sections are informative.\fP +.SH APPLICATION USAGE +.LP +The obsolescent \fB-\fP \fInumber\fP form is withdrawn in this version. +Applications should use the \fB-n\fP \fInumber\fP +option. +.SH EXAMPLES +.LP +To write the first ten lines of all files (except those with a leading +period) in the directory: +.sp +.RS +.nf + +\fBhead * +\fP +.fi +.RE +.SH RATIONALE +.LP +Although it is possible to simulate \fIhead\fP with \fIsed\fP 10q +for a single file, the +standard developers decided that the popularity of \fIhead\fP on historical +BSD systems warranted its inclusion alongside \fItail\fP. +.LP +This standard version of \fIhead\fP follows the Utility Syntax Guidelines. +The \fB-n\fP option was added to this new interface +so that \fIhead\fP and \fItail\fP would be more logically related. +.LP +There is no \fB-c\fP option (as there is in \fItail\fP) because it +is not historical +practice and because other utilities in this volume of IEEE\ Std\ 1003.1-2001 +provide similar functionality. +.SH FUTURE DIRECTIONS +.LP +None. +.SH SEE ALSO +.LP +\fIsed\fP, \fItail\fP +.SH COPYRIGHT +Portions of this text are reprinted and reproduced in electronic form +from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 6, Copyright (C) 2001-2003 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 . |