TRUNCATE(2)                                                        TRUNCATE(2)



NAME
       truncate - truncate a file to a specified length

SYNOPSIS
       truncate(path, length)
       char *path;
       off_t length;

       ftruncate(fd, length)
       int fd;
       off_t length;

DESCRIPTION
       _T_r_u_n_c_a_t_e  causes the file named by _p_a_t_h or referenced by _f_d to be trun‐
       cated to at most _l_e_n_g_t_h bytes in size.   If  the  file  previously  was
       larger  than  this  size,  the extra data is lost.  With _f_t_r_u_n_c_a_t_e, the
       file must be open for writing.

RETURN VALUES
       A value of 0 is returned if the call succeeds.  If the call fails a  -1
       is returned, and the global variable _e_r_r_n_o specifies the error.

ERRORS
       _T_r_u_n_c_a_t_e succeeds unless:

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

       [EINVAL]       The  pathname  contains  a character with the high-order
                      bit set.

       [ENAMETOOLONG] A component of a pathname exceeded 255 characters, or an
                      entire path name exceeded 1023 characters.

       [ENOENT]       The named file does not exist.

       [EACCES]       Search  permission is denied for a component of the path
                      prefix.

       [EACCES]       The named file is not writable by the user.

       [ELOOP]        Too many symbolic links were encountered in  translating
                      the pathname.

       [EISDIR]       The named file is a directory.

       [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.

       [EIO]          An I/O error occurred updating the inode.

       [EFAULT]       _P_a_t_h points  outside  the  process’s  allocated  address
                      space.

       _F_t_r_u_n_c_a_t_e succeeds unless:

       [EBADF]        The _f_d is not a valid descriptor.

       [EINVAL]       The _f_d references a socket, not a file.

       [EINVAL]       The _f_d is not open for writing.

SEE ALSO
       open(2)

BUGS
       These calls should be generalized to allow ranges of bytes in a file to
       be discarded.



4.2 Berkeley Distribution       March 29, 1986                     TRUNCATE(2)