Another binary manipulation thread. Post: 302849007

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Top Forums UNIX for Advanced & Expert Users Another binary manipulation thread. Post 302849007 by DGPickett on Friday 30th of August 2013 03:37:47 PM

08-30-2013

Registered User

There is a wealth of possibilities, between the readline options, stty raw, and IFS, but so many tools do not deal with null, it's hard to even test. If you bash "read =n 1" a null into a variable, is it hard to tell the variable is the empty string '' or ""?

To write it out, one might use the printf character option, treating it as a special case and providing the null as a zero char (int) value. Once you get to treating it as a special case, you can write it with something like "echo '\0\c' ".

$IFS characters are another challenge, but if you use "read -n 1" you could do your own $IFS processing if any, setting $IFS to '' or unsetting it.

DGPickett

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copystr

copystr(9r)															       copystr(9r)

NAME

       copystr - General: Copies a null-terminated character string with a specified limit

SYNOPSIS

       int copystr(
	       char *s1,
	       char *s2,
	       u_int maxlength,
	       u_int *ncopiedaddr );

ARGUMENTS

       Specifies  a  pointer  to  a  string  (an array of characters terminated by a null character).  Specifies a pointer to a buffer of at least
       maxlength characters.  Specifies the maximum number of characters to copy.  Specifies the address of an integer to receive  the	number	of
       copied characters.

DESCRIPTION

       The  copystr  routine  copies  string  s1 to the buffer pointed to by s2. The routine stops after copying a null character or after copying
       maxlength characters, whichever comes first. The s2 buffer is not padded with null characters to maxlength.

       The copystr routine returns the number of characters copied in the location pointed to by ncopiedaddr. Note that the character  size  is  1
       byte.

RETURN VALUES

       Upon  successful  completion,  copystr  returns	the  value  0 (zero). Otherwise, it can return the following error: The string length, s1,
       exceeds the maximum number of characters, maxlength.

SEE ALSO

       Routines: bcopy(9r), blkclr(9r), ovbcopy(9r), strcpy(9r), strncpy(9r)

																       copystr(9r)