man22 - 11/3/71 NAME SYNOPSIS DESCRIPTION mount - mount...

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11/3/71 SYS MOUNT (II) NAME mount -- mount file system SYNOPSIS sys mount; special; name / mount = 21.; not in assembler DESCRIPTION mount announces to the system that a removable file system has been mounted on special file special; from now on, references to file name will refer to the root file on the newly mounted file system. Special and name are pointers to null—terminated strings containing the appropriate path names. Name must exist already. If it had useful contents, they are inaccessible while the file system is mounted. Almost always, name should be a directory so that an entire file system, not just one file, may exist on the removable device. FILES SEE ALSO umount DIAGNOSTICS Error bit (c—bit) set if special is inaccessible or dir does not exist. BUGS At most one removable device can be mounted at a time. The use of this call should be restricted to the super—user. OWNER ken, dmr
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11/3/71 SYS OPEN (II) NAME open -- open for reading or writing SYNOPSIS sys open; name; mode / open = 5. (descriptor in r0) DESCRIPTION open opens the file name for reading (if mode is 0) or writing (if mode is non—zero), name is the address of a string of ASCII characters representing a path name, terminated by a null character. The file descriptor should be saved for subsequent calls to read (or write) and close. In both the read and write case the file pointer is set to the beginning of the file. If the last link to an open file is removed, the file is not destroyed until it is closed. FILES SEE ALSO creat, read, write, close DIAGNOSTICS The error bit (c—bit) is set if the file does not exist, if one of the necessary directories does not exist or is unreadable, or if the file is not readable. B UGS OWNER ken, dmr
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11/3/71 SYS QUIT (II) NAME quit -- turn off quit signal SYNOPSIS sys quit; flag / quit = 26. DESCRIPTION When flag is 0, this call disables quit signals from the typewriter (ASCII FS). When flag is 1, quits are re—enabled, and cause execution to cease and a core image to be produced. When flag is an address in the program, a quit causes control to be sent to that address. Quits should be turned off only with due consideration. FILES SEE ALSO sys intr turns off interrupts DIAGNOSTICS BUGS OWNER ken, dmr
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11/3/71 SYS READ (II) NAME read -- read from file SYNOPSIS (file descriptor in r0) sys read; buffer; nchars / read = 3. (nread in r0) DESCRIPTION A file descriptor is a word returned from a successful open call. Buffer is the location of nchars contiguous bytes into which the input will be placed. It is not guaranteed that all nchars bytes will be read, however; for example if the file refers to a typewriter at most one line will be returned. In any event the number of characters read is returned in r0. If r0 returns with value 0, then end—of—file has been reached.
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man22 - 11/3/71 NAME SYNOPSIS DESCRIPTION mount - mount...

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