08-30-2006
Problem with read & write
Hello mates:
I met problem with using read() & write(). I m trying to use read twice on client first time is the size of buffer, 2nd time is the buffer. I think I have to, coz I dnot know file size. So, I write twice on server as well -- 1st, filesize; 2nd, buffer.
The problem is, sometimes, I cannot get anything at 2nd time. The file I got is empty, nothing. However, if I put a sleep(1) before the 2nd write() on server, I can read( but this sometimes may cause a segmentation fault)...
i.e.:
Client Server
read() 1st write() 1st <-----both OK
(if I put a sleep(1)here, it's OK)
read() 2d write() 2nd <-----problem
Does anybody know the reason?
BEST REGARDS,
Elton
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LEARN ABOUT OSF1
telecode
telecode(5) File Formats Manual telecode(5)
NAME
telecode - A character encoding system (codeset) for Traditional Chinese
DESCRIPTION
The Telecode codeset (called Mitac Telex in early versions of the operating system) consists of 2 character planes. Each character plane
has 8836 character positions. In plane 1, standard characters occupy positions 0001 to 8045; the remaining 791 positions are for user-
defined characters. In plane 2, standard characters occupy positions 0001 to 8489; the remaining 346 positions are for user-defined charac-
ters. Telecode uses 2-byte values to represent characters on both planes.
Plane 1 Character Encoding
To differentiate plane 1 code from plane 2 code, the most significant bit (MSB) is set on in both bytes of a plane 1 character code. The
following formula calculates the value of a plane 1 character from its position on the plane:
1st byte = M + 161
2nd byte = N + 161 - M x 94
In this formula, N is the position of the character and M = N / 94.
For example, if a character is at position 2502 on plane 1, its encoding value is BBDB, which is calculated as follows:
N = 2502, M = 2502/94 = 26 1st byte = 26 + 161 = 187 2nd byte = 2502 + 161 - 26 x 94 = 219
Plane 2 Character Encoding
To differentiate plane 2 code from plane 1 code, the MSB of the first byte is set on and that of the second byte is set off for each plane
2 character code. The following formula calculates the value of a plane 2 character from its position:
1st byte = M + 161
2nd byte = N + 33 - M x 94
In this formula, N is the position of the character on the plane and M = N / 94.
For example, if a character is at position 2502 on plane 2, its encoding value is BB5B, which is calculated as follows:
N = 2502, M = 2502/94 = 26 1st byte = 26 + 161 = 187 2nd byte = 2502 + 33 - 26 x 94 = 91
Codeset Conversion
The following codeset converter pairs are available for converting Traditional Chinese characters between telecode and other encoding for-
mats. Refer to iconv_intro(5) for an introduction to codeset conversion. For more information about the other codeset for which telecode
is the input or output, see the reference page specified in the list item. big5_telecode, telecode_big5
Converting from and to the Big-5 codeset: big5(5).
Note that Big-5 encoding is equivalent to the Microsoft code-page format used on PCs for Traditional Chinese. You can therefore use
these converters to convert Traditional Chinese characters between PC code page format and Telecode encoding format. For more infor-
mation on how the operating system supports PC code pages, see code_page(5). dechanyu_telecode, telecode_dechanyu
Converting from and to the DEC Hanyu codeset: dechanyu(5). eucTW_telecode, telecode_eucTW
Converting from and to Taiwanese Extended UNIX Code: eucTW(5).
Font Support for Telecode
The operating system supports Telecode only through conversion to another codeset.
SEE ALSO
Commands: locale(1)
Others: ascii(5), big5(5), Chinese(5), code_page(5), dechanyu(5), dechanzi(5), eucTW(5), GBK(5), i18n_intro(5), i18n_printing(5),
iconv_intro(5), l10n_intro(5), sbig5(5)
telecode(5)