PMSTRNCPY(3)               Library Functions Manual               PMSTRNCPY(3)

NAME
       pmstrncpy - safe string copy

C SYNOPSIS
       #include <pcp/pmapi.h>

       int pmstrncpy(char *dest, size_t destlen, char *src);

       cc ... -lpcp

DESCRIPTION
       pmstrncpy is safe string copying routine with semantics similar to
       strncpy(3).

       The main differences between pmstrncpy and strncpy(3) are:
       o src must be null-byte terminated for pmstrncpy
       o pmstrncpy ensures that dest is null-byte terminated, even when src is
         larger than destlen; this may result in truncated copying of src
       o when src is shorter than destlen pmstrncpy does not null-byte fill
         the remainder of dest after src has been copied and null-byte
         terminated
       o the length argument has the same semantics for pmstrncpy and
         pmstrncat(3), unlike strncpy(3) and strncat(3).
       o the return value from pmstrncpy is useful
       o the order of the arguments for pmstrncpy has been deliberately
         changed from the order of the arguments for strncpy(3) to avoid
         accidental misuse that a compiler can easily detect

       On success, pmstrncpy returns 0, else -1 indicates that src is too big
       and the result been truncated to ensure dest has not been overrun.

HISTORY
       strncpy(3) first appeared in Edition 7 AT&T Unix around 1979.  It was
       specifically crafted to copy file names from component names from on-
       disk directory entries that were of a fixed maximum size and may have
       zero, one or more trailing null-bytes

       The subsequent attempts to use strncpy(3) for more generally string
       copying operations has been fraught with abuse and security issues;
       pmstrncpy is an attempt to address these problems.

SEE ALSO
       PMAPI(3), pmstrncat(3), strncat(3) and strncpy(3).

Performance Co-Pilot                  PCP                         PMSTRNCPY(3)