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|00000000| 5c 73 65 63 74 69 6f 6e | 7b 42 75 69 6c 74 2d 69 |\section|{Built-i|
|00000010| 6e 20 4d 6f 64 75 6c 65 | 20 5c 73 65 63 74 63 6f |n Module| \sectco|
|00000020| 64 65 7b 74 68 72 65 61 | 64 7d 7d 0d 5c 62 69 6d |de{threa|d}}.\bim|
|00000030| 6f 64 69 6e 64 65 78 7b | 74 68 72 65 61 64 7d 0d |odindex{|thread}.|
|00000040| 0d 54 68 69 73 20 6d 6f | 64 75 6c 65 20 70 72 6f |.This mo|dule pro|
|00000050| 76 69 64 65 73 20 6c 6f | 77 2d 6c 65 76 65 6c 20 |vides lo|w-level |
|00000060| 70 72 69 6d 69 74 69 76 | 65 73 20 66 6f 72 20 77 |primitiv|es for w|
|00000070| 6f 72 6b 69 6e 67 20 77 | 69 74 68 20 6d 75 6c 74 |orking w|ith mult|
|00000080| 69 70 6c 65 0d 74 68 72 | 65 61 64 73 20 28 61 2e |iple.thr|eads (a.|
|00000090| 6b 2e 61 2e 20 5c 64 66 | 6e 7b 6c 69 67 68 74 2d |k.a. \df|n{light-|
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|000000b0| 7d 20 6f 72 20 5c 64 66 | 6e 7b 74 61 73 6b 73 7d |} or \df|n{tasks}|
|000000c0| 29 20 2d 2d 2d 20 6d 75 | 6c 74 69 70 6c 65 0d 74 |) --- mu|ltiple.t|
|000000d0| 68 72 65 61 64 73 20 6f | 66 20 63 6f 6e 74 72 6f |hreads o|f contro|
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|000000f0| 67 6c 6f 62 61 6c 20 64 | 61 74 61 20 73 70 61 63 |global d|ata spac|
|00000100| 65 2e 20 20 46 6f 72 0d | 73 79 6e 63 68 72 6f 6e |e.  For.|synchron|
|00000110| 69 7a 61 74 69 6f 6e 2c | 20 73 69 6d 70 6c 65 20 |ization,| simple |
|00000120| 6c 6f 63 6b 73 20 28 61 | 2e 6b 2e 61 2e 20 5c 64 |locks (a|.k.a. \d|
|00000130| 66 6e 7b 6d 75 74 65 78 | 65 73 7d 20 6f 72 20 5c |fn{mutex|es} or \|
|00000140| 64 66 6e 7b 62 69 6e 61 | 72 79 0d 73 65 6d 61 70 |dfn{bina|ry.semap|
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|00000170| 65 20 69 73 20 6f 70 74 | 69 6f 6e 61 6c 20 61 6e |e is opt|ional an|
|00000180| 64 20 73 75 70 70 6f 72 | 74 65 64 20 6f 6e 20 53 |d suppor|ted on S|
|00000190| 47 49 20 49 52 49 58 20 | 34 2e 78 20 61 6e 64 20 |GI IRIX |4.x and |
|000001a0| 35 2e 78 20 61 6e 64 20 | 53 75 6e 0d 53 6f 6c 61 |5.x and |Sun.Sola|
|000001b0| 72 69 73 20 32 2e 78 20 | 73 79 73 74 65 6d 73 2c |ris 2.x |systems,|
|000001c0| 20 61 73 20 77 65 6c 6c | 20 61 73 20 6f 6e 20 73 | as well| as on s|
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|000001f0| 6d 65 6e 74 61 74 69 6f | 6e 20 28 65 2e 67 2e 20 |mentatio|n (e.g. |
|00000200| 4b 53 52 29 2e 0d 0d 49 | 74 20 64 65 66 69 6e 65 |KSR)...I|t define|
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|00000220| 63 6f 6e 73 74 61 6e 74 | 20 61 6e 64 20 66 75 6e |constant| and fun|
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|00000240| 6f 6d 6d 61 6e 64 7b 5c | 69 6e 64 65 78 73 75 62 |ommand{\|indexsub|
|00000250| 69 74 65 6d 7d 7b 28 69 | 6e 20 6d 6f 64 75 6c 65 |item}{(i|n module|
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|00000270| 7b 65 78 63 64 65 73 63 | 7d 7b 65 72 72 6f 72 7d |{excdesc|}{error}|
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|00000290| 64 2d 73 70 65 63 69 66 | 69 63 20 65 72 72 6f 72 |d-specif|ic error|
|000002a0| 73 2e 0d 5c 65 6e 64 7b | 65 78 63 64 65 73 63 7d |s..\end{|excdesc}|
|000002b0| 0d 0d 5c 62 65 67 69 6e | 7b 66 75 6e 63 64 65 73 |..\begin|{funcdes|
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|00000310| 6e 63 74 69 6f 6e 20 5c | 76 61 72 7b 66 75 6e 63 |nction \|var{func|
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|00000430| 64 7b 66 75 6e 63 64 65 | 73 63 7d 0d 0d 5c 62 65 |d{funcde|sc}..\be|
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|00000480| 4f 74 68 65 72 20 74 68 | 72 65 61 64 73 20 63 6f |Other th|reads co|
|00000490| 6e 74 69 6e 75 65 20 74 | 6f 20 72 75 6e 2e 0d 5c |ntinue t|o run..\|
|000004a0| 73 74 72 6f 6e 67 7b 43 | 61 76 65 61 74 3a 7d 20 |strong{C|aveat:} |
|000004b0| 63 6f 64 65 20 69 6e 20 | 70 65 6e 64 69 6e 67 20 |code in |pending |
|000004c0| 5c 63 6f 64 65 7b 66 69 | 6e 61 6c 6c 79 7d 20 63 |\code{fi|nally} c|
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|00000500| 75 6e 63 64 65 73 63 7d | 7b 65 78 69 74 5f 70 72 |uncdesc}|{exit_pr|
|00000510| 6f 67 7d 7b 73 74 61 74 | 75 73 7d 0d 45 78 69 74 |og}{stat|us}.Exit|
|00000520| 20 61 6c 6c 20 74 68 72 | 65 61 64 73 20 61 6e 64 | all thr|eads and|
|00000530| 20 72 65 70 6f 72 74 20 | 74 68 65 20 76 61 6c 75 | report |the valu|
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|00000550| 20 61 72 67 75 6d 65 6e | 74 0d 5c 76 61 72 7b 73 | argumen|t.\var{s|
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|00000590| 0d 5c 73 74 72 6f 6e 67 | 7b 43 61 76 65 61 74 3a |.\strong|{Caveat:|
|000005a0| 7d 20 63 6f 64 65 20 69 | 6e 20 70 65 6e 64 69 6e |} code i|n pendin|
|000005b0| 67 20 5c 63 6f 64 65 7b | 66 69 6e 61 6c 6c 79 7d |g \code{|finally}|
|000005c0| 20 63 6c 61 75 73 65 73 | 2c 20 69 6e 20 74 68 69 | clauses|, in thi|
|000005d0| 73 20 74 68 72 65 61 64 | 0d 6f 72 20 69 6e 20 6f |s thread|.or in o|
|000005e0| 74 68 65 72 20 74 68 72 | 65 61 64 73 2c 20 69 73 |ther thr|eads, is|
|000005f0| 20 6e 6f 74 20 65 78 65 | 63 75 74 65 64 2e 0d 5c | not exe|cuted..\|
|00000600| 65 6e 64 7b 66 75 6e 63 | 64 65 73 63 7d 0d 0d 5c |end{func|desc}..\|
|00000610| 62 65 67 69 6e 7b 66 75 | 6e 63 64 65 73 63 7d 7b |begin{fu|ncdesc}{|
|00000620| 61 6c 6c 6f 63 61 74 65 | 5f 6c 6f 63 6b 7d 7b 7d |allocate|_lock}{}|
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|000007a0| 6e 74 69 66 69 65 72 73 | 20 6d 61 79 20 62 65 20 |ntifiers| may be |
|000007b0| 72 65 63 79 63 6c 65 64 | 20 77 68 65 6e 20 61 20 |recycled| when a |
|000007c0| 74 68 72 65 61 64 20 65 | 78 69 74 73 20 61 6e 64 |thread e|xits and|
|000007d0| 0d 61 6e 6f 74 68 65 72 | 20 74 68 72 65 61 64 20 |.another| thread |
|000007e0| 69 73 20 63 72 65 61 74 | 65 64 2e 0d 5c 65 6e 64 |is creat|ed..\end|
|000007f0| 7b 66 75 6e 63 64 65 73 | 63 7d 0d 0d 4c 6f 63 6b |{funcdes|c}..Lock|
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|00000830| 61 6e 64 7b 5c 69 6e 64 | 65 78 73 75 62 69 74 65 |and{\ind|exsubite|
|00000840| 6d 7d 7b 28 6c 6f 63 6b | 20 6d 65 74 68 6f 64 29 |m}{(lock| method)|
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|00000ab0| 64 20 73 75 63 63 65 73 | 73 66 75 6c 6c 79 2c 20 |d succes|sfully, |
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|00000bd0| 30 20 69 66 20 6e 6f 74 | 2e 0d 5c 65 6e 64 7b 66 |0 if not|..\end{f|
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|00000c00| 7b 69 74 65 6d 69 7a 65 | 7d 0d 5c 69 74 65 6d 0d |{itemize|}.\item.|
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|00000c60| 6f 6e 20 77 69 6c 6c 20 | 62 65 20 72 65 63 65 69 |on will |be recei|
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|00000d00| 20 74 6f 20 63 61 6c 6c | 69 6e 67 0d 5c 63 6f 64 | to call|ing.\cod|
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|00000d20| 6f 67 28 5c 76 61 72 7b | 73 74 61 74 75 73 7d 29 |og(\var{|status})|
|00000d30| 7d 2c 20 65 78 63 65 70 | 74 20 74 68 61 74 20 74 |}, excep|t that t|
|00000d40| 68 65 20 66 6f 72 6d 65 | 72 20 77 61 79 73 20 6f |he forme|r ways o|
|00000d50| 66 0d 65 78 69 74 69 6e | 67 20 74 68 65 20 65 6e |f.exitin|g the en|
|00000d60| 74 69 72 65 20 70 72 6f | 67 72 61 6d 20 64 6f 20 |tire pro|gram do |
|00000d70| 68 6f 6e 6f 72 20 5c 63 | 6f 64 65 7b 66 69 6e 61 |honor \c|ode{fina|
|00000d80| 6c 6c 79 7d 20 63 6c 61 | 75 73 65 73 20 69 6e 20 |lly} cla|uses in |
|00000d90| 74 68 65 0d 63 75 72 72 | 65 6e 74 20 74 68 72 65 |the.curr|ent thre|
|00000da0| 61 64 20 28 62 75 74 20 | 6e 6f 74 20 69 6e 20 6f |ad (but |not in o|
|00000db0| 74 68 65 72 20 74 68 72 | 65 61 64 73 29 2e 0d 0d |ther thr|eads)...|
|00000dc0| 5c 69 74 65 6d 0d 4e 6f | 74 20 61 6c 6c 20 62 75 |\item.No|t all bu|
|00000dd0| 69 6c 74 2d 69 6e 20 66 | 75 6e 63 74 69 6f 6e 73 |ilt-in f|unctions|
|00000de0| 20 74 68 61 74 20 6d 61 | 79 20 62 6c 6f 63 6b 20 | that ma|y block |
|00000df0| 77 61 69 74 69 6e 67 20 | 66 6f 72 20 49 2f 4f 20 |waiting |for I/O |
|00000e00| 61 6c 6c 6f 77 20 6f 74 | 68 65 72 0d 74 68 72 65 |allow ot|her.thre|
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|00000e20| 6f 75 67 68 20 74 68 65 | 20 6d 6f 73 74 20 70 6f |ough the| most po|
|00000e30| 70 75 6c 61 72 20 6f 6e | 65 73 20 28 5c 63 6f 64 |pular on|es (\cod|
|00000e40| 65 7b 73 6c 65 65 70 7d | 2c 0d 5c 63 6f 64 65 7b |e{sleep}|,.\code{|
|00000e50| 72 65 61 64 7d 2c 20 5c | 63 6f 64 65 7b 73 65 6c |read}, \|code{sel|
|00000e60| 65 63 74 7d 29 20 77 6f | 72 6b 20 61 73 20 65 78 |ect}) wo|rk as ex|
|00000e70| 70 65 63 74 65 64 2e 0d | 0d 5c 65 6e 64 7b 69 74 |pected..|.\end{it|
|00000e80| 65 6d 69 7a 65 7d 0d    |                         |emize}. |        |
+--------+-------------------------+-------------------------+--------+--------+