PATHCHK(1) User Commands PATHCHK(1)


NAME


pathchk - check path names

SYNOPSIS


pathchk [-p] path...


DESCRIPTION


The pathchk command will check that one or more path names are valid
(that is, they could be used to access or create a file without causing
syntax errors) and portable (that is, no filename truncation will
result). More extensive portability checks are provided by the -p option.


By default, pathchk will check each component of each path operand based
on the underlying file system. A diagnostic will be written for each path
operand that:

o is longer than PATH_MAX bytes.

o contains any component longer than NAME_MAX bytes in its
containing directory

o contains any component in a directory that is not searchable

o contains any character in any component that is not valid in
its containing directory.


The format of the diagnostic message is not specified, but will indicate
the error detected and the corresponding path operand.


It will not be considered an error if one or more components of a path
operand do not exist as long as a file matching the path name specified
by the missing components could be created that does not violate any of
the checks specified above.

OPTIONS


The following option is supported:

-p
Instead of performing checks based on the underlying file system,
write a diagnostic for each path operand that:

o is longer than _POSIX_PATH_MAX bytes

o contains any component longer than _POSIX_NAME_MAX bytes

o contains any character in any component that is not in
the portable filename character set.


OPERANDS


The following operand is supported:

path
A path to be checked.


USAGE


See largefile(7) for the description of the behavior of pathchk when
encountering files greater than or equal to 2 Gbyte ( 2^31 bytes).

EXAMPLES


Example 1: Using the pathchk command




To verify that all paths in an imported data interchange archive are
legitimate and unambiguous on the current system:


example% pax -f archive | sed -e '/ == .*/s///' | xargs pathchk
if [ $? -eq 0 ]
then
pax -r -f archive
else
echo Investigate problems before importing files.
exit 1
fi


To verify that all files in the current directory hierarchy could be
moved to any system conforming to the X/Open specification that also
supports the pax(1) command:


example% find . -print | xargs pathchk -p
if [ $? -eq 0 ]
then
pax -w -f archive .
else
echo Portable archive cannot be created.
exit 1
fi


To verify that a user-supplied path names a readable file and that the
application can create a file extending the given path without truncation
and without overwriting any existing file:


example% case $- in
*C*) reset="";;
*) reset="set +C"
set -C;;
esac
test -r "$path" && pathchk "$path.out" &&
rm "$path.out" > "$path.out"
if [ $? -ne 0 ]; then
printf "%s: %s not found or %s.out fails \
creation checks.\n" $0 "$path" "$path"
$reset # reset the noclobber option in case a trap
# on EXIT depends on it
exit 1
fi
$reset
PROCESSING < "$path" > "$path.out"


The following assumptions are made in this example:


1. PROCESSING represents the code that will be used by the
application to use $path once it is verified that $path.out
will work as intended.

2. The state of the noclobber option is unknown when this code is
invoked and should be set on exit to the state it was in when
this code was invoked. (The reset variable is used in this
example to restore the initial state.)

3. Note the usage of:

rm "$path.out" > "$path.out"


a.
The pathchk command has already verified, at this point, that
$path.out will not be truncated.


b.
With the noclobber option set, the shell will verify that
$path.out does not already exist before invoking rm.


c.
If the shell succeeded in creating $path.out, rm will remove it
so that the application can create the file again in the
PROCESSING step.


d.
If the PROCESSING step wants the file to exist already when it
is invoked, the:

rm "$path.out" > "$path.out"


should be replaced with:

> "$path.out"


which will verify that the file did not already exist, but
leave $path.out in place for use by PROCESSING.


ENVIRONMENT VARIABLES


See environ(7) for descriptions of the following environment variables
that affect the execution of pathchk: LANG, LC_ALL, LC_CTYPE,
LC_MESSAGES, and NLSPATH.

EXIT STATUS


The following exit values are returned:

0
All path operands passed all of the checks.


>0
An error occurred.


ATTRIBUTES


See attributes(7) for descriptions of the following attributes:


+--------------------+-----------------+
| ATTRIBUTE TYPE | ATTRIBUTE VALUE |
+--------------------+-----------------+
|Interface Stability | Standard |
+--------------------+-----------------+

SEE ALSO


pax(1), test(1), attributes(7), environ(7), largefile(7), standards(7)


February 1, 1995 PATHCHK(1)