08-29-2005
Null Characters
How do I get rid of null characters/strings in a unix text file. I need to use this in a script. When I use dev/null it puts null characters in my file and makes it larger. Please help
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tar(4) Kernel Interfaces Manual tar(4)
NAME
tar - format of tar tape archive
DESCRIPTION
The header structure produced by (see tar(1)) is as follows (the array size defined by the constants is shown on the right):
All characters are represented in ASCII. There is no padding used in the header block; all fields are contiguous.
The fields magic, uname, and gname are null-terminated character strings. The fields name, linkname, and prefix are null-terminated char-
acter strings except when all characters in the array contain non-null characters, including the last character. The version field is two
bytes containing the characters (zero-zero). The typeflag contains a single character. All other fields are leading-zero-filled octal
numbers in ASCII. Each numeric field is terminated by one or more space or null characters.
The name and the prefix fields produce the pathname of the file. The hierarchical relationship of the file is retained by specifying the
pathname as a path prefix, with a slash character and filename as the suffix. If the prefix contains non-null characters, prefix, a slash
character, and name are concatenated without modification or addition of new characters to produce a new pathname. In this manner, path-
names of at most 256 characters can be supported. If a pathname does not fit in the space provided, the format-creating utility notifies
the user of the error, and no attempt is made to store any part of the file, header, or data on the medium.
SEE ALSO
tar(1)
STANDARDS CONFORMANCE
tar(4)