obi less: now actually behaves like less

python/obitools3/commands/less.pyx

@@ -1,9 +1,17 @@
 #cython: language_level=3
 
-from obitools3.apps.optiongroups import addMinimalInputOption
+from obitools3.apps.progress cimport ProgressBar  # @UnresolvedImport
 from obitools3.uri.decode import open_uri
 from obitools3.dms import DMS
+from obitools3.utils cimport tobytes
+from obitools3.dms.capi.obiview cimport QUALITY_COLUMN
+from obitools3.apps.optiongroups import addMinimalInputOption
 
+import sys
+import io
+from subprocess import Popen, PIPE
+
+from cpython.exc cimport PyErr_CheckSignals
 
 __title__="Less equivalent"
 
@@ -12,33 +20,31 @@ def addOptions(parser):
     
     addMinimalInputOption(parser)
 
-    group=parser.add_argument_group('obi less specific options')
- 
-    group.add_argument('--print', '-n',
-                     action="store", dest="less:print",
-                     metavar='<N>',
-                     default=10,
-                     type=int,
-                     help="Print N entries (default: 10)")
- 
 
 def run(config):
         
-    cdef object entries
-    cdef int    n
-    
     DMS.obi_atexit()
         
+    # Open the input
     input = open_uri(config['obi']['inputURI'])
+    if input is None:
+        raise Exception("Could not read input")
+    iview = input[1]
     
-    entries = input[1]
+    process = Popen(["less"], stdin=PIPE)
     
-    if config['less']['print'] > len(entries) :
-        n = len(entries)
-    else :
-        n = config['less']['print']
+    for seq in iview :
+        PyErr_CheckSignals()
+        try:
+            process.stdin.write(tobytes(repr(seq)))
+            process.stdin.write(b"\n")
+        except (StopIteration, BrokenPipeError, IOError):
+            break
 
-    # Print
-    for i in range(n) :
-        print(repr(entries[i]))
+    sys.stderr.close()
+    process.stdin.close()
+    process.wait()
+
+    iview.close()
+    input[0].close()