mfc@s|dZyddlmZWnek r3dZnXdgZdZdd dYZdZedkrxend S( s File-like objects that read from or write to a string buffer. This implements (nearly) all stdio methods. f = StringIO() # ready for writing f = StringIO(buf) # ready for reading f.close() # explicitly release resources held flag = f.isatty() # always false pos = f.tell() # get current position f.seek(pos) # set current position f.seek(pos, mode) # mode 0: absolute; 1: relative; 2: relative to EOF buf = f.read() # read until EOF buf = f.read(n) # read up to n bytes buf = f.readline() # read until end of line ('\n') or EOF list = f.readlines()# list of f.readline() results until EOF f.truncate([size]) # truncate file at to at most size (default: current pos) f.write(buf) # write at current position f.writelines(list) # for line in list: f.write(line) f.getvalue() # return whole file's contents as a string Notes: - Using a real file is often faster (but less convenient). - There's also a much faster implementation in C, called cStringIO, but it's not subclassable. - fileno() is left unimplemented so that code which uses it triggers an exception early. - Seeking far beyond EOF and then writing will insert real null bytes that occupy space in the buffer. - There's a simple test set (see end of this file). i(tEINVALitStringIOcCs|rtdndS(NsI/O operation on closed file(t ValueError(tclosed((s /usr/lib64/python2.7/StringIO.pyt_complain_ifclosed&scBseZdZddZdZdZdZdZddZd Z d d Z dd Z dd Z ddZdZdZdZdZRS(sclass StringIO([buffer]) When a StringIO object is created, it can be initialized to an existing string by passing the string to the constructor. If no string is given, the StringIO will start empty. The StringIO object can accept either Unicode or 8-bit strings, but mixing the two may take some care. If both are used, 8-bit strings that cannot be interpreted as 7-bit ASCII (that use the 8th bit) will cause a UnicodeError to be raised when getvalue() is called. tcCs^t|tst|}n||_t||_g|_d|_t|_d|_ dS(Ni( t isinstancet basestringtstrtbuftlentbuflisttpostFalseRt softspace(tselfR ((s /usr/lib64/python2.7/StringIO.pyt__init__6s    cCs|S(N((R((s /usr/lib64/python2.7/StringIO.pyt__iter__AscCs,t|j|j}|s(tn|S(s_A file object is its own iterator, for example iter(f) returns f (unless f is closed). When a file is used as an iterator, typically in a for loop (for example, for line in f: print line), the next() method is called repeatedly. This method returns the next input line, or raises StopIteration when EOF is hit. (RRtreadlinet StopIteration(Rtr((s /usr/lib64/python2.7/StringIO.pytnextDs    cCs%|js!t|_|`|`ndS(s Free the memory buffer. N(RtTrueR R (R((s /usr/lib64/python2.7/StringIO.pytcloseQs  cCst|jtS(s_Returns False because StringIO objects are not connected to a tty-like device. (RRR (R((s /usr/lib64/python2.7/StringIO.pytisattyXs icCst|j|jr=|jdj|j7_g|_n|dkrY||j7}n|dkru||j7}ntd||_dS(sSet the file's current position. The mode argument is optional and defaults to 0 (absolute file positioning); other values are 1 (seek relative to the current position) and 2 (seek relative to the file's end). There is no return value. RiiiN(RRR R tjoinR R tmax(RR tmode((s /usr/lib64/python2.7/StringIO.pytseek_s     cCst|j|jS(s#Return the file's current position.(RRR (R((s /usr/lib64/python2.7/StringIO.pyttellrs icCst|j|jr=|jdj|j7_g|_n|dksU|dkra|j}nt|j||j}|j|j|!}||_|S(sERead at most size bytes from the file (less if the read hits EOF before obtaining size bytes). If the size argument is negative or omitted, read all data until EOF is reached. The bytes are returned as a string object. An empty string is returned when EOF is encountered immediately. RiN( RRR R RtNoneR tminR (RtntnewposR((s /usr/lib64/python2.7/StringIO.pytreadws     cCst|j|jr=|jdj|j7_g|_n|jjd|j}|dkrm|j}n |d}|dk r|dkr|j||kr|j|}qn|j|j|!}||_|S(s%Read one entire line from the file. A trailing newline character is kept in the string (but may be absent when a file ends with an incomplete line). If the size argument is present and non-negative, it is a maximum byte count (including the trailing newline) and an incomplete line may be returned. An empty string is returned only when EOF is encountered immediately. Note: Unlike stdio's fgets(), the returned string contains null characters ('\0') if they occurred in the input. Rs iiN( RRR R RtfindR R R(RtlengthtiR!R((s /usr/lib64/python2.7/StringIO.pyRs       cCsrd}g}|j}xS|rm|j||t|7}d|koU|knr^Pn|j}qW|S(s'Read until EOF using readline() and return a list containing the lines thus read. If the optional sizehint argument is present, instead of reading up to EOF, whole lines totalling approximately sizehint bytes (or more to accommodate a final whole line). i(RtappendR (Rtsizehintttotaltlinestline((s /usr/lib64/python2.7/StringIO.pyt readliness   cCs~t|j|dkr%|j}n9|dkrCttdn||jkr^||_n|j| |_||_dS(sTruncate the file's size. If the optional size argument is present, the file is truncated to (at most) that size. The size defaults to the current position. The current file position is not changed unless the position is beyond the new file size. If the specified size exceeds the file's current size, the file remains unchanged. isNegative size not allowedN( RRRR tIOErrorRtgetvalueR R (Rtsize((s /usr/lib64/python2.7/StringIO.pyttruncates     cCs^t|j|sdSt|ts5t|}n|j}|j}||kr|jj||t||_|_dS||kr|jjd|||}n|t|}||kr2|jr|j dj |j7_ n|j | ||j |g|_d|_ ||krH|}qHn|jj||}||_||_dS(sGWrite a string to the file. There is no return value. NtR( RRRRRR R R R&R R(RtstspostslenR!((s /usr/lib64/python2.7/StringIO.pytwrites4             cCs(|j}x|D]}||qWdS(sWrite a sequence of strings to the file. The sequence can be any iterable object producing strings, typically a list of strings. There is no return value. (The name is intended to match readlines(); writelines() does not add line separators.) N(R4(RtiterableR4R*((s /usr/lib64/python2.7/StringIO.pyt writeliness  cCst|jdS(s"Flush the internal buffer N(RR(R((s /usr/lib64/python2.7/StringIO.pytflushscCsDt|j|jr=|jdj|j7_g|_n|jS(s Retrieve the entire contents of the "file" at any time before the StringIO object's close() method is called. The StringIO object can accept either Unicode or 8-bit strings, but mixing the two may take some care. If both are used, 8-bit strings that cannot be interpreted as 7-bit ASCII (that use the 8th bit) will cause a UnicodeError to be raised when getvalue() is called. R(RRR R R(R((s /usr/lib64/python2.7/StringIO.pyR-s   N(t__name__t __module__t__doc__RRRRRRRR"RRR+R/R4R6R7R-(((s /usr/lib64/python2.7/StringIO.pyR*s            ! c Csddl}|jdr)|jd}nd}t|dj}t|dj}t}x|d D]}|j|qmW|j|d|j|krt dn|j }dG|GH|j t |d|j|d|j dd Gt |jGHd G|j GH|j}d Gt |GH|j t | d|jt |}||krt d n|j t |d|j}|d}|j |j t ||j}||krt d ndGt |GdGHdG|j GH|j |kr-t dn|j|d|j dddG|j GH|j |dkrt dn|jdS(Niis /etc/passwdRis write faileds File length =is First line =s Position =s Second line =sbad result after seek backs#bad result after seek back from EOFtReads more liness bad lengthisTruncated length =struncate did not adjust length(tsystargvtopenR+R"RR4R6R-t RuntimeErrorRRR treprRR/R( R<tfileR)ttexttfR*R$tline2tlist((s /usr/lib64/python2.7/StringIO.pyttestsT                 t__main__N(( R:terrnoRt ImportErrort__all__RRRFR8(((s /usr/lib64/python2.7/StringIO.pyts     -