diff options
Diffstat (limited to 'txr.1')
| -rw-r--r-- | txr.1 | 96 |
1 files changed, 94 insertions, 2 deletions
@@ -8726,6 +8726,21 @@ For example (logand -2 7) produces 6. This is because -2 is ..111110 in infinite-bit two's-complement. Or-ing this value with 7 (111) produces 110. +.SS Functions logtest + +.TP +Syntax: + + (logtest <int1> <int2>) + +.TP +Description: + +The logtest function returns true if <int1> and <int1> have bits in +common. The following equivalence holds: + + (logtest a b) <--> (not (zerop (logand a b))) + .SS Functions lognot and logtrunc .TP @@ -9285,8 +9300,9 @@ symbols in the program. (op foo @rest @1) -> (lambda (arg1 . rest) [foo rest arg1]) -.TP +.PP +.TP Examples: ;; Take a list of pairs and produce a list in which those pairs @@ -9555,6 +9571,8 @@ number. If the precision is omitted, then the number of digits after the decimal point is three. If the precision is zero, then a decimal portion is truncated off entirely, including the decimal point. +.PP + .SS Functions print, pprint, tostring, tostringp .TP @@ -9751,6 +9769,8 @@ values in the range 0 to 255. Note that if a stream supports both byte input and character input, then mixing the two operations will interfere with the UTF-8 decoding. +These functions return nil when the end of data is reached. Errors are +represented as exceptions. .SS Functions put-string, put-line, put-char and put-byte .TP @@ -9799,9 +9819,81 @@ meaningful, it does nothing. .SS Function stat +.TP +Syntax: + + (stat <path>) + +.TP +Description: + +The stat function inquires the filesystem about the existence of an object +denoted by the string <path>. If the object is not found or cannot be +accessed, an exception is thrown. + +Otherwise information is retrieved about the object. The information takes the +form of a property list in which keyword symbols denote numerous properties. +An example such property list is (:dev 2049 :ino 669944 :mode 16832 :nlink 23 +:uid 500 :gid 500 :rdev 0 :size 12288 :blksize 4096 :blocks 24 :atime +1347933533 :mtime 1347933534 :ctime 1347933534) + +These properties correspond to the similarly-named entires of the struct stat +structure in POSIX. For instance, the :dev property has the same value +as the st_dev field. + +.SS The variables s-ifmt s-iflnk s-ifreg s-ifblk ... s-ixoth + +The following variables exist, having integer values. These are bitmasks +which can be applied against the value given by the :mode property +in the property list returned by the function stat: s-ifmt, s-iflnk, s-ifreg, +s-ifblk, s-ifdir, s-ifchr, s-ififo, s-isuid, s-isgid, s-isvtx, s-irwxu, +s-irusr, s-iwusr, s-ixusr, s-irwxg, s-irgrp, s-iwgrp, s-ixgrp, s-irwxo, +s-iroth, s-iwoth and s-ixoth. + +These variables correspond to the C constants S_IFMT, S_IFLNK, S_IFREG +and so forth. + +The logtest function can be used to test these against values of mode. +For example (logtest mode s-irgrp) tests for the group read permission. + .SS Function open-directory -.SS Functions open-file +.TP +Syntax: + + (open-directory <path>) + +.TP +Description: + +The open-directory function tries to create a stream which reads the +directory given by the string argument <path>. If a filesystem object exists +under the path, is accessible, and is a directory, then the function +returns a stream. Otherwise, a file error exception is thrown. + +The resulting stream supports the get-line operation. Each call to the +get-line operation retrieves a string representing the next directory +entry. The value nil is returned when there are no more directory entries. +The . and .. entries in Unix filesystems are not skipped. + +.SS Function open-file + +.TP +Syntax: + + (open-file <path> <mode-string>) + +.TP +Description: + +The open-file function creates a stream connected to the file +which is located at the given <path>, which is a string. +The <mode-string> argument is a string which uses the same +conventions as the mode argument of the C language fopen function. +The mode string determines whether the stream is an input stream +or output stream. Note that the "b" mode is not supported. +Whether a stream is text or binary depends on which operations +are invoked on it. .SH COPROCESSES |