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diff --git a/man-pages-posix-2013/man1p/cmp.1p b/man-pages-posix-2013/man1p/cmp.1p new file mode 100644 index 0000000..1157d60 --- /dev/null +++ b/man-pages-posix-2013/man1p/cmp.1p @@ -0,0 +1,269 @@ +'\" et +.TH CMP "1P" 2013 "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 +cmp +\(em compare two files +.SH SYNOPSIS +.LP +.nf +cmp \fB[\fR\(mil|\(mis\fB] \fIfile1 file2\fR +.fi +.SH DESCRIPTION +The +.IR cmp +utility shall compare two files. The +.IR cmp +utility shall write no output if the files are the same. Under default +options, if they differ, it shall write to standard output the byte and +line number at which the first difference occurred. Bytes and lines +shall be numbered beginning with 1. +.SH OPTIONS +The +.IR cmp +utility shall conform to the Base Definitions volume of POSIX.1\(hy2008, +.IR "Section 12.2" ", " "Utility Syntax Guidelines". +.P +The following options shall be supported: +.IP "\fB\(mil\fP" 10 +(Lowercase ell.) Write the byte number (decimal) and the differing +bytes (octal) for each difference. +.IP "\fB\(mis\fP" 10 +Write nothing for differing files; return exit status only. +.SH OPERANDS +The following operands shall be supported: +.IP "\fIfile1\fR" 10 +A pathname of the first file to be compared. If +.IR file1 +is +.BR '\(mi' , +the standard input shall be used. +.IP "\fIfile2\fR" 10 +A pathname of the second file to be compared. If +.IR file2 +is +.BR '\(mi' , +the standard input shall be used. +.P +If both +.IR file1 +and +.IR file2 +refer to standard input or refer to the same FIFO special, block +special, or character special file, the results are undefined. +.SH STDIN +The standard input shall be used only if the +.IR file1 +or +.IR file2 +operand refers to standard input. See the INPUT FILES section. +.SH "INPUT FILES" +The input files can be any file type. +.SH "ENVIRONMENT VARIABLES" +The following environment variables shall affect the execution of +.IR cmp : +.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\(hy2008, +.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). +.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 and +informative messages written to standard output. +.IP "\fINLSPATH\fP" 10 +Determine the location of message catalogs for the processing of +.IR LC_MESSAGES . +.SH "ASYNCHRONOUS EVENTS" +Default. +.SH STDOUT +In the POSIX locale, results of the comparison shall be written to +standard output. When no options are used, the format shall be: +.sp +.RS 4 +.nf +\fB +"%s %s differ: char %d, line %d\en", \fIfile1\fR, \fIfile2\fR, + <\fIbyte number\fR>, <\fIline number\fR> +.fi \fR +.P +.RE +.P +When the +.BR \(mil +option is used, the format shall be: +.sp +.RS 4 +.nf +\fB +"%d %o %o\en", <\fIbyte number\fR>, <\fIdiffering byte\fR>, + <\fIdiffering byte\fR> +.fi \fR +.P +.RE +.P +for each byte that differs. The first <\fIdiffering\ byte\fP> number is +from +.IR file1 +while the second is from +.IR file2 . +In both cases, <\fIbyte\ number\fP> shall be relative to the beginning +of the file, beginning with 1. +.P +No output shall be written to standard output when the +.BR \(mis +option is used. +.SH STDERR +The standard error shall be used only for diagnostic messages. If the +.BR \(mil +option is used and +.IR file1 +and +.IR file2 +differ in length, or if the +.BR \(mis +option is not used and +.IR file1 +and +.IR file2 +are identical for the entire length of the shorter file, in the POSIX +locale the following diagnostic message shall be written: +.sp +.RS 4 +.nf +\fB +"cmp: EOF on %s%s\en", <\fIname of shorter file\fR>, <\fIadditional info\fR> +.fi \fR +.P +.RE +.P +The <\fIadditional\ info\fP> field shall either be null or a string +that starts with a +<blank> +and contains no +<newline> +characters. Some implementations report on the number of lines in +this case. +.SH "OUTPUT FILES" +None. +.SH "EXTENDED DESCRIPTION" +None. +.SH "EXIT STATUS" +The following exit values shall be returned: +.IP "\00" 6 +The files are identical. +.IP "\01" 6 +The files are different; this includes the case where one file is +identical to the first part of the other. +.IP >1 6 +An error occurred. +.SH "CONSEQUENCES OF ERRORS" +Default. +.LP +.IR "The following sections are informative." +.SH "APPLICATION USAGE" +Although input files to +.IR cmp +can be any type, the results might not be what would be expected on +character special device files or on file types not described by the +System Interfaces volume of POSIX.1\(hy2008. Since this volume of POSIX.1\(hy2008 does not specify the block size used when doing +input, comparisons of character special files need not compare all of +the data in those files. +.P +For files which are not text files, line numbers simply reflect the +presence of a +<newline>, +without any implication that the file is organized into lines. +.SH EXAMPLES +None. +.SH RATIONALE +The global language in +.IR "Section 1.4" ", " "Utility Description Defaults" +indicates that using two mutually-exclusive options together produces +unspecified results. Some System V implementations consider the option +usage: +.sp +.RS 4 +.nf +\fB +cmp \(mil \(mis ... +.fi \fR +.P +.RE +.P +to be an error. They also treat: +.sp +.RS 4 +.nf +\fB +cmp \(mis \(mil ... +.fi \fR +.P +.RE +.P +as if no options were specified. Both of these behaviors are +considered bugs, but are allowed. +.P +The word +.BR char +in the standard output format comes from historical usage, even though +it is actually a byte number. When +.IR cmp +is supported in other locales, implementations are encouraged to use +the word +.IR byte +or its equivalent in another language. Users should not interpret this +difference to indicate that the functionality of the utility changed +between locales. +.P +Some implementations report on the number of lines in the +identical-but-shorter file case. This is allowed by the inclusion of +the <\fIadditional\ info\fP> fields in the output format. The +restriction on having a leading +<blank> +and no +<newline> +characters is to make parsing for the filename easier. It is recognized +that some filenames containing white-space characters make parsing +difficult anyway, but the restriction does aid programs used on systems +where the names are predominantly well behaved. +.SH "FUTURE DIRECTIONS" +None. +.SH "SEE ALSO" +.IR "\fIcomm\fR\^", +.IR "\fIdiff\fR\^" +.P +The Base Definitions volume of POSIX.1\(hy2008, +.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, 2013 Edition, Standard for Information Technology +-- Portable Operating System Interface (POSIX), The Open Group Base +Specifications Issue 7, Copyright (C) 2013 by the Institute of +Electrical and Electronics Engineers, Inc and The Open Group. +(This is POSIX.1-2008 with the 2013 Technical Corrigendum 1 applied.) 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.unix.org/online.html . + +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 . |