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Manuál Linux
[Linux manuál]

val: ověření souborů SCCS (VÝVOJ)

Originální popis anglicky: val - validate SCCS files ( DEVELOPMENT)

Návod, kniha: POSIX Programmer's Manual


val -
val [-s][-m name ][-r SID ][-y type] file...


The val utility shall determine whether the specified file is an SCCS file meeting the characteristics specified by the options.


The val utility shall conform to the Base Definitions volume of IEEE Std 1003.1-2001, Section 12.2, Utility Syntax Guidelines, except that the usage of the '-' operand is not strictly as intended by the guidelines (that is, reading options and operands from standard input).
The following options shall be supported:
-m  name
Specify a name, which is compared with the SCCS %M% keyword in file; see get .
-r  SID
Specify a SID (SCCS Identification String), an SCCS delta number. A check shall be made to determine whether the SID is ambiguous (for example, -r 1 is ambiguous because it physically does not exist but implies 1.1, 1.2, and so on, which may exist) or invalid (for example, -r 1.0 or -r 1.1.0 are invalid because neither case can exist as a valid delta number). If the SID is valid and not ambiguous, a check shall be made to determine whether it actually exists.
Silence the diagnostic message normally written to standard output for any error that is detected while processing each named file on a given command line.
-y  type
Specify a type, which shall be compared with the SCCS % Y% keyword in file; see get .


The following operands shall be supported:
A pathname of an existing SCCS file. If exactly one file operand appears, and it is '-' , the standard input shall be read: each line shall be independently processed as if it were a command line argument list. (However, the line is not subjected to any of the shell word expansions, such as parameter expansion or quote removal.)


The standard input shall be a text file used only when the file operand is specified as '-' .


Any SCCS files processed shall be files of an unspecified format.


The following environment variables shall affect the execution of val:
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.)
If set to a non-empty string value, override the values of all the other internationalization variables.
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).
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.
Determine the location of message catalogs for the processing of LC_MESSAGES .




The standard output shall consist of informative messages about either:
Each file processed
Each command line read from standard input
If the standard input is not used, for each file operand yielding a discrepancy, the output line shall have the following format:
"%s: %s\n", <pathname>, <unspecified string>
If standard input is used, a line of input shall be written before each of the preceding lines for files containing discrepancies:
"%s:\n", <input line>


Not used.






The 8-bit code returned by val shall be a disjunction of the possible errors; that is, it can be interpreted as a bit string where set bits are interpreted as follows:
0x80 = Missing file argument.
0x40 = Unknown or duplicate option.
0x20 = Corrupted SCCS file.
0x10 = Cannot open file or file not SCCS.
0x08 = SID is invalid or ambiguous.
0x04 = SID does not exist.
0x02 = %Y%, -y mismatch.
0x01 = %M%, -m mismatch.
Note that val can process two or more files on a given command line and can process multiple command lines (when reading the standard input). In these cases an aggregate code shall be returned: a logical OR of the codes generated for each command line and file processed.


The following sections are informative.


Since the val exit status sets the 0x80 bit, shell applications checking "$?" cannot tell if it terminated due to a missing file argument or receipt of a signal.


In a directory with three SCCS files- s.x (of t type "text"), s.y, and s.z (a corrupted file)-the following command could produce the output shown:
val - <<EOF -y source s.x -m y s.y s.z EOF
-y source s.x
s.x: %Y%, -y mismatch s.z
s.z: corrupted SCCS file






admin , delta , get , prs 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 .
2003 IEEE/The Open Group
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