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diff --git a/coreutils-5.3.0-bin/man/cat1p/cat.1p.txt b/coreutils-5.3.0-bin/man/cat1p/cat.1p.txt new file mode 100644 index 0000000..f71aef6 --- /dev/null +++ b/coreutils-5.3.0-bin/man/cat1p/cat.1p.txt @@ -0,0 +1,248 @@ +cat(P) cat(P) + + + + + +NAME + cat - concatenate and print files + +SYNOPSIS + cat [-u][file ...] + +DESCRIPTION + The cat utility shall read files in sequence and shall + write their contents to the standard output in the same + sequence. + +OPTIONS + The cat utility shall conform to the Base Definitions + volume of IEEE Std 1003.1-2001, Section 12.2, Utility + Syntax Guidelines. + + The following option shall be supported: + + -u Write bytes from the input file to the standard + output without delay as each is read. + + +OPERANDS + The following operand shall be supported: + + file A pathname of an input file. If no file operands + are specified, the standard input shall be used. + If a file is '-' , the cat utility shall read + from the standard input at that point in the + sequence. The cat utility shall not close and + reopen standard input when it is referenced in + this way, but shall accept multiple occurrences + of '-' as a file operand. + + +STDIN + The standard input shall be used only if no file oper- + ands are specified, or if a file operand is '-' . See + the INPUT FILES section. + +INPUT FILES + The input files can be any file type. + +ENVIRONMENT VARIABLES + The following environment variables shall affect the + execution of cat: + + 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 . + + +ASYNCHRONOUS EVENTS + Default. + +STDOUT + The standard output shall contain the sequence of bytes + read from the input files. Nothing else shall be written + to the standard output. + +STDERR + The standard error shall be used only for diagnostic + messages. + +OUTPUT FILES + None. + +EXTENDED DESCRIPTION + None. + +EXIT STATUS + The following exit values shall be returned: + + 0 All input files were output successfully. + + >0 An error occurred. + + +CONSEQUENCES OF ERRORS + Default. + + The following sections are informative. + +APPLICATION USAGE + The -u option has value in prototyping non-blocking + reads from FIFOs. The intent is to support the following + sequence: + + + mkfifo foo + cat -u foo > /dev/tty13 & + cat -u > foo + + It is unspecified whether standard output is or is not + buffered in the default case. This is sometimes of + interest when standard output is associated with a ter- + minal, since buffering may delay the output. The pres- + ence of the -u option guarantees that unbuffered I/O is + available. It is implementation-defined whether the cat + utility buffers output if the -u option is not speci- + fied. Traditionally, the -u option is implemented using + the equivalent of the setvbuf() function defined in the + System Interfaces volume of IEEE Std 1003.1-2001. + +EXAMPLES + The following command: + + + cat myfile + + writes the contents of the file myfile to standard + output. + + The following command: + + + cat doc1 doc2 > doc.all + + concatenates the files doc1 and doc2 and writes the + result to doc.all. + + Because of the shell language mechanism used to perform + output redirection, a command such as this: + + + cat doc doc.end > doc + + causes the original data in doc to be lost. + + The command: + + + cat start - middle - end > file + + when standard input is a terminal, gets two arbitrary + pieces of input from the terminal with a single invoca- + tion of cat. Note, however, that if standard input is a + regular file, this would be equivalent to the command: + + + cat start - middle /dev/null end > file + + because the entire contents of the file would be con- + sumed by cat the first time '-' was used as a file oper- + and and an end-of-file condition would be detected imme- + diately when '-' was referenced the second time. + +RATIONALE + Historical versions of the cat utility include the + options -e, -t, and -v, which permit the ends of lines, + <tab>s, and invisible characters, respectively, to be + rendered visible in the output. The standard developers + omitted these options because they provide too fine a + degree of control over what is made visible, and similar + output can be obtained using a command such as: + + + sed -n -e 's/$/$/' -e l pathname + + The -s option was omitted because it corresponds to dif- + ferent functions in BSD and System V-based systems. The + BSD -s option to squeeze blank lines can be accomplished + by the shell script shown in the following example: + + + sed -n ' + # Write non-empty lines. + /./ { + p + d + } + # Write a single empty line, then look for more empty lines. + /^$/ p + # Get next line, discard the held <newline> (empty line), + # and look for more empty lines. + :Empty + /^$/ { + N + s/.// + b Empty + } + # Write the non-empty line before going back to search + # for the first in a set of empty lines. + p + + The System V -s option to silence error messages can be + accomplished by redirecting the standard error. Note + that the BSD documentation for cat uses the term "blank + line" to mean the same as the POSIX "empty line'': a + line consisting only of a <newline>. + + The BSD -n option was omitted because similar function- + ality can be obtained from the -n option of the pr util- + ity. + +FUTURE DIRECTIONS + None. + +SEE ALSO + more , the System Interfaces volume of + IEEE Std 1003.1-2001, setvbuf() + +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 cat(P) |