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mirror of https://github.com/DoctorWkt/unix-jun72.git synced 2026-01-11 23:53:34 +00:00
2008-05-02 17:50:21 +00:00

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clr u.break
mov r5,sp / point sp to user's stack
mov $14,u.count
mov $u.off,u.fofp
clr u.off / set offset in file to be read to zero
jsr r0,readi / read in first six words of user's file, starting
/ at $core
mov sp,r5 / put users stack address in r5
sub $core+40.,r5 / subtract $core +40, from r5 (leaves
/ number of words less 26 available for
/ program in user core
mov r5,u.count /
cmp core,$405 / br .+14 is first instruction if file is
/ standard a.out format
bne 1f / branch, if not standard format
mov core+2,r5 / put 2nd word of users program in r5; number of
/ bytes in program text
sub $14,r5 / subtract 12
cmp r5,u.count /
bgt 1f / branch if r5 greater than u.count
mov r5,u.count
jsr r0,readi / read in rest of user's program text
add core+10,u.nread / add size of user data area to u.nread
br 2f
1:
jsr r0,readi / read in rest of file
2:
mov u.nread,u.break / set users program break to end of
/ user code
add $core+14,u.break / plus data area
jsr r0,iclose / does nothing
br sysret3 / return to core image at $core
sysfstat: / set status of open file
jsr r0,arg; u.off / put buffer address in u.off
mov u.off,-(sp) / put buffer address on the stack
mov *u.r0,r1 / put file descriptor in r1
jsr r0,getf / get the files i-number
tst r1 / is it 0?
beq error3 / yes, error
bgt 1f / if i-number is negative (open for writing)
neg r1 / make it positive, then branch
br 1f / to 1f
sysstat: / ; name of file; buffer - get files status
jsr r0,arg2 / get the 2 arguments
jsr r0,namei / get the i-number for the file
br error3 / no such file, error
1:
jsr r0,iget / get the i-node into core
mov (sp)+,r3 / move u.off to r3 (points to buffer)
mov r1,(r3)+ / put i-number in 1st word of buffer
mov $inode,r2 / r2 points to i-node
1:
mov (r2)+,(r3)+ / move rest of i-node to buffer
cmp r2,$inode+32 / done?