truncate64 man page on Raspbian

Man page or keyword search:  
man Server   8174 pages
apropos Keyword Search (all sections)
Output format
Raspbian logo
[printable version]

TRUNCATE(2)		   Linux Programmer's Manual		   TRUNCATE(2)

NAME
       truncate, ftruncate - truncate a file to a specified length

SYNOPSIS
       #include <unistd.h>
       #include <sys/types.h>

       int truncate(const char *path, off_t length);
       int ftruncate(int fd, off_t length);

   Feature Test Macro Requirements for glibc (see feature_test_macros(7)):

       truncate():
	   Since glibc 2.12
	       _BSD_SOURCE || _XOPEN_SOURCE >= 500 ||
	       _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED ||
	       _POSIX_C_SOURCE >= 200809L
	   Before glibc 2.12:
	       _BSD_SOURCE || _XOPEN_SOURCE >= 500 ||
	       _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED

       ftruncate():
	   Since glibc 2.12:
	       _BSD_SOURCE || _XOPEN_SOURCE >= 500 ||
	       _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED ||
	       _POSIX_C_SOURCE >= 200809L
	   Between glibc 2.3.5 and 2.11
	       _BSD_SOURCE || _XOPEN_SOURCE >= 500 ||
	       _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED ||
	       _POSIX_C_SOURCE >= 200112L
	   Before glibc 2.3.5:
	       _BSD_SOURCE || _XOPEN_SOURCE >= 500 ||
	       _XOPEN_SOURCE && _XOPEN_SOURCE_EXTENDED

DESCRIPTION
       The  truncate()	and ftruncate() functions cause the regular
       file named by path or referenced by fd to be truncated to  a
       size of precisely length bytes.

       If  the file previously was larger than this size, the extra
       data is lost.  If the file previously  was  shorter,  it	 is
       extended, and the extended part reads as null bytes ('\0').

       The file offset is not changed.

       If  the	size changed, then the st_ctime and st_mtime fields
       (respectively, time of last status change and time  of  last
       modification; see stat(2)) for the file are updated, and the
       set-user-ID and set-group-ID permission bits may be cleared.

       With ftruncate(), the file must be open	for  writing;  with
       truncate(), the file must be writable.

RETURN VALUE
       On success, zero is returned.  On error, -1 is returned, and
       errno is set appropriately.

ERRORS
       For truncate():

       EACCES Search permission is denied for a	 component  of	the
	      path prefix, or the named file is not writable by the
	      user.  (See also path_resolution(7).)

       EFAULT Path points outside the process's	 allocated  address
	      space.

       EFBIG  The  argument  length is larger than the maximum file
	      size. (XSI)

       EINTR  A signal was caught during execution.

       EINVAL The argument length is negative or  larger  than	the
	      maximum file size.

       EIO    An I/O error occurred updating the inode.

       EINTR  While  blocked  waiting  to  complete,  the  call was
	      interrupted by a signal  handler;	 see  fcntl(2)	and
	      signal(7).

       EISDIR The named file is a directory.

       ELOOP  Too many symbolic links were encountered in translat‐
	      ing the pathname.

       ENAMETOOLONG
	      A component of a pathname exceeded 255 characters, or
	      an entire pathname exceeded 1023 characters.

       ENOENT The named file does not exist.

       ENOTDIR
	      A component of the path prefix is not a directory.

       EPERM  The underlying file system does not support extending
	      a file beyond its current size.

       EROFS  The named file resides on a read-only file system.

       ETXTBSY
	      The file is a pure procedure (shared text) file  that
	      is being executed.

       For ftruncate() the same errors apply, but instead of things
       that can be wrong with path, we now have things that can	 be
       wrong with the file descriptor, fd:

       EBADF  fd is not a valid descriptor.

       EBADF or EINVAL
	      fd is not open for writing.

       EINVAL fd does not reference a regular file.

CONFORMING TO
       4.4BSD,	SVr4,  POSIX.1-2001  (these calls first appeared in
       4.2BSD).

NOTES
       The above description is	 for  XSI-compliant  systems.	For
       non-XSI-compliant  systems,  the	 POSIX	standard allows two
       behaviors for  ftruncate()  when	 length	 exceeds  the  file
       length (note that truncate() is not specified at all in such
       an environment): either returning an error, or extending the
       file.  Like most Unix implementations, Linux follows the XSI
       requirement when dealing with native file systems.  However,
       some  nonnative	file  systems  do not permit truncate() and
       ftruncate() to be used to extend a file beyond  its  current
       length: a notable example on Linux is VFAT.

SEE ALSO
       open(2), stat(2), path_resolution(7)

COLOPHON
       This  page  is  part  of release 3.27 of the Linux man-pages
       project.	 A description	of  the	 project,  and	information
       about  reporting	 bugs,	can  be	 found	at  http://www.ker‐
       nel.org/doc/man-pages/.

Linux				  2010-09-20			   TRUNCATE(2)
[top]

List of man pages available for Raspbian

Copyright (c) for man pages and the logo by the respective OS vendor.

For those who want to learn more, the polarhome community provides shell access and support.

[legal] [privacy] [GNU] [policy] [cookies] [netiquette] [sponsors] [FAQ]
Tweet
Polarhome, production since 1999.
Member of Polarhome portal.
Based on Fawad Halim's script.
....................................................................
Vote for polarhome
Free Shell Accounts :: the biggest list on the net