<!DOCTYPE html><html lang="en-US"><head><title>Just a moment...</title><meta http-equiv="Content-Type" content="text/html; charset=UTF-8"><meta http-equiv="X-UA-Compatible" content="IE=Edge"><meta name="robots" content="noindex,nofollow"><meta name="viewport" content="width=device-width,initial-scale=1"><style>*{box-sizing:border-box;margin:0;padding:0}html{line-height:1.15;-webkit-text-size-adjust:100%;color:#313131;font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue",Arial,"Noto Sans",sans-serif,"Apple Color Emoji","Segoe UI Emoji","Segoe UI Symbol","Noto Color Emoji"}body{display:flex;flex-direction:column;height:100vh;min-height:100vh}.main-content{margin:8rem auto;padding-left:1.5rem;max-width:60rem}@media (width <= 720px){.main-content{margin-top:4rem}}.h2{line-height:2.25rem;font-size:1.5rem;font-weight:500}@media (width <= 720px){.h2{line-height:1.5rem;font-size:1.25rem}}#challenge-error-text{background-image:url("data:image/svg+xml;base64,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");background-repeat:no-repeat;background-size:contain;padding-left:34px}@media (prefers-color-scheme: dark){body{background-color:#222;color:#d9d9d9}}</style><meta http-equiv="refresh" content="360"></head><body><div class="main-wrapper" role="main"><div class="main-content"><noscript><div class="h2"><span id="challenge-error-text">Enable JavaScript and cookies to continue</span></div></noscript></div></div><script>(function(){window._cf_chl_opt = {cvId: '3',cZone: 'sourceforge.net',cType: 'managed',cRay: '95e1444114d2f84d',cH: 'dbLHS7YQ72hT6gGU3U1d0Jp1SJ2J.iz77brLGISYqKE-1752330921-1.2.1.1-gQid0pU.6SYW11Y08mj.cFTldgYfBz_DH4PQvIdFI9GA7s_LG3wtA8Ln9YK1t02W',cUPMDTk:"\/p\/xsb\/src\/1564\/tree\/\/trunk\/XSB\/docs\/userman\/library.tex?__cf_chl_tk=kb6_fKtk97bzuAaYqQ6BvVxn22.0r32x21YuYN4XJ.M-1752330921-1.0.1.1-MyD4r5mpiR80eDJQgC8uOXzYIRJYUWm9Yx0t26yg2Gk",cFPWv: 'g',cITimeS: '1752330921',cTplC:0,cTplV:5,cTplB: 'cf',fa:"\/p\/xsb\/src\/1564\/tree\/\/trunk\/XSB\/docs\/userman\/library.tex?__cf_chl_f_tk=kb6_fKtk97bzuAaYqQ6BvVxn22.0r32x21YuYN4XJ.M-1752330921-1.0.1.1-MyD4r5mpiR80eDJQgC8uOXzYIRJYUWm9Yx0t26yg2Gk",md: 'd9n8lSP4Xn.xFlJvgl4rDDvwnoRq8N3BA992g8NGKDo-1752330921-1.2.1.1-iwZimy6lcZ.HSvbqKUE7pVnYTIiOwNr3tcOAKa_hQYPHwnc8CQiBgM61aVSwjMmxcHuZ5g31laaN0UIomC4rq3D46l0jVvQ216yFg60ZQV4zzc5FHYOVZ5tUE6Gf6.pj.AhTZ7AoX7.DYjNBmv9NDEsEFFARGuSjTyvkAThSujRhZzxPqXZ40bKKlu90zIzO_zABC.cBhhxW.TaYbG800.N.rssK3FUmQSK7qZiLooE2ITuJq2u5HfGiodOjXI.MfkCdkfuxTwt0e0646Z6QVDplKZ.5cVLKM9NDECj6BvW2aH.QUdxpAC6n.E4Ac8IoCxIlkhnusxqFjNq3Yv8JqEYoNOkiZH7ZGWps41VwrYbMR0OnLegscF3WRewiL_CBYTwsDEOfP4x0QFrHCykj5Id.BkgWm5hu3KSTcGgEUkn56.75xfPpxLMsf8qKx04X5LwBDzDjVveMTttNCIK2XbN3WF1I_VH6GGOryRYElhdXFWQxQjkk6Xb9i3SeVzs0B75.DXyyWn3D3.T7LdEjEZPbZ5hZGeP9.TlPLYHBvDF.lufLWl_m1gQsNDrODVWA0ecXcDvFLnAe8OcDaMJ2gxfN.9Scc_t0bZwOB8pU8gVzk_jfy11IeARRt0rXth6dH4KK.v6y.NpR2On.Otr9lG4e71Cy0z9z7qj1liTnV4wrxIpxC8LE_WULvIL5hF_UyXF3OlBm8nnjng5lnyBeVganrUag3h8zWIsbpSeMT58T2DYnZBvIpAd02JO9wvuFBET0Ck5p2wsrZzUA.lZEL4IcecjG80U2MF5Dghwr4POcUZqCJjsEgE0RugWAmYx_P8Bs1CN9a1q6MsXRgoc.._6zFe3tmfbzxFmax8RCALNFLivlbNs1ELkUqQexNJD5yQuBMnx0h2aaA493tS29qp7k3jVkUTtALaDGQ5hMvXsDgQBYF4nVDampwfnXnC6OA.U2R96vr5kYzs8dLybXatuvJ3GYNJV0268WmcyOHiA',mdrd: 'oALqKWmg7K68T_uwkEoNWYcMtSNv6q3FDRGNeNvsZ4M-1752330921-1.2.1.1-E21RnTsgXszZKSwlWhCs5aH7WB16PRNXFrBFqLh6TrJZKa45kB5RGRk4bBSsmWHPKNeaBfDO5x0kEi0eUmiwbTDaMxC6e6tmT7qE8w8lgH3awe0h2Ws.OzKouQDTSyZoyiMrpynIrhJw7W7FYblyVN6jlVjPn7lF3XeZh91vmnvGMiPQT3JX1E4ZaM61rwv4ZI_QWTUbrGw5dNVBLdi1MpsLaMDK2ytPFeJRi_4z7I5tDrd543EGQYkcFfaLGM7WkZLYPJ1LWmMYwJ4UkCa6PCs662_tR3U1QW7q8ow_yyKvZw4ejp0Emfli.W3jD5eBvPngeoxZXBjI8yV7OkosrVvJSPEWbJRGk8P_ls4yjPZEQxqBiQnj9E6HYdV_s5FR29SG68XSRm4sIQZDlMF._iW8k2YdaOwq65EX8T0Pu.4m7x5N4IUN4rd7BAMgT4cHmDMvwOSZ1.GvOPaEfqCwseJRxSdUxxMDonvnkamEic6Rbonn0QcbQx.a.Cf1tF.mhYZ_n8B57uKMioZHTWhfmI8r6s6fI5OBXkrPVRplAn0BW7d0qfSIoSRNbaqrjTkYrvFq1QbS0E9dkbJROKSxKmVHmtz_XAQkB6ekacpgbP6LNGgB.KDnubJcqiYF_0r1K5he3ywsjaUkmNZIE3sSxxTsdXKfUSWLdKWv9QbGW63Het9g_fZlRxdriWpmeVrtCda9PufGgEAUh2knVI21fFlXQbaJYNylivQ0aEPp9B_IJQ7Beexde7Gmx5HwfLhtVC.EsRfm_XzUqCTQoVeaF4rzu7LM84drNXAh8MassHo4bzvFRQpLFfGacxSvpGbsLJ8Y0vIlzu47npn6xocpeucpn6waCaWaYNNSUw_2Fy8gGhNIzd.wElsw7lqJQgSThFSDfq63vk9mdTivyU3gPS.NmNGdax8GXJMw3LQ75WQpZdGUSLOi7fZg2cHcwKtG_6wz_hU9kPIksJqdIJxter4vM4_cHlTzfyAfkZMDVTY_2uPhvKBeA5DAWTG7zpbOrkVwfRBc6pQ5hwEaIADFmQN6vS0qtemNPd6wxaq2YGyj5QCzwwQrnFm9mfuCRznQPvEpKrADXx0S7qdocdbwhpqHQEj1p9k1J5abBMdZzB9HzhNx3KoY9wDwKQm_77dflXOztrHayjN5tyb8oVANz8O_lEAxK70RHXOW7q9ocAltvhIL93ILBVpVL7n4cYdG_vGyw4_7R.ecQRzfMFugxyomm7BJM7EpptaxpAfgkmDJeejJUN7ReRO_jSVl0WJ5Wihf9LbCwFDClR_DVhlpjxKJDbGjz6rknaKicNrt6Jn_ejZ3ZGq5U4vufdEq0KIfh6CQ9XnKD_YMjuq9AzWU0BZUcpORiYJitIeuiegXPXwhN2pHcYfSk.5SBD.mpEawm6liZCpqInVbPYj3AaxJ2.RflH.ni.1Vl9jSoT7s3PxHlb4As4rZt6ItDAfFywrjoMg8QCLJv0MjuxjjtkbVtPIhKWZCJQJPAqgjigEHO_w1alAS7XuCkwKVl5.yUzkHSFusM10LVcD0FwOuVuno5fabfRCXzyZ9WmD8I9NyMfndoy_uvXPBBvEKXwBDHDLIU_PSN7q7ChLhBZ4eydkNKkoxTIXSh5Is1UQEtA6Ajl4pSxfb962t3NDdf7eGQ7iIL3TQooluEun0wiuYBANYAa0lds2ATI_FDBnyDyeypkq3HK8w.hIeq3F6aclwmjylfs5ZZZIQTV3QqOrPXdv_OZMUDQok8V35cJzccXBL0Vz2m79U2qdFJe7XprRSKTKPO3.5v5eFX85YvKc0hZnECV3lTkovoTa7srlaqg8EkOSeQhFrJa81iHf.VzBUgsPegLPVu0tv6BF2JLp2jOSMJWZXMex.zqKIcsldXEOReNakworK.RPaEzvw9YUvuGqyRQ3fOmflqDp_xBT8.0S4PAzI_CYnvZhlGCzV4zpNY5sn9Jzi3C38AqbBj6045kAdpHC0wExUOEiyX4tftf0EasGM3g7nM.pbjl4pihgi15CZajmz5ApqGkW8xZpt4g.f.bwjj6fS0Up4hIwgMRXE8MSWQn.Tj1ZTN0g1eQjF4eEj4tiozTVMbfmedKbuGx954S4bKAi9bhDDvzBT9mnI2LCMyKc5EruGz0xAaYiLs_3H8YUQHU.1GcqkpCR7dnIdTtpdh_pxbuF9qjNnhSuL9Kx8mihf7eUniu9ctWgQYta9aiW7B0_zz_V7ri55ytxEQrKdFSYEuzousWo8pY3btorQCSUH39FTYJzF_rHN4IuwKTc7inAp6l1mZq8oGT74vA94DO1Z5OIwZnFx9NrNRd6qa3IsAKYRLAEBjNwb6nE6qIT7hDzOKgbIuZRU0PTZKKHClKUB3sUyh1hOBldRBYOwXyMb9SvDIUt_jmfFrL8pALBuhqdOKIussZ40te8RX0HchO44.0wgi9qx6fynaPAxZLUMX6l8amnM5YKTUEqI2JaaKY5r6rQmLFVVn6V7TSvfcQDDV2kmkt86wpysukM0_oPxumcwgU825VF47qPXwe7u3Xnw97FiGPEqN8ohXPzjcY1J8ayi1T6ipCYYSshX3HGkmSl4VgZ95UAfEww',};var a = document.createElement('script');a.src = '/cdn-cgi/challenge-platform/h/g/orchestrate/chl_page/v1?ray=95e1444114d2f84d';window._cf_chl_opt.cOgUHash = location.hash === '' && location.href.indexOf('#') !== -1 ? '#' : location.hash;window._cf_chl_opt.cOgUQuery = location.search === '' && location.href.slice(0, location.href.length - window._cf_chl_opt.cOgUHash.length).indexOf('?') !== -1 ? '?' : location.search;if (window.history && window.history.replaceState) {var ogU = location.pathname + window._cf_chl_opt.cOgUQuery + window._cf_chl_opt.cOgUHash;history.replaceState(null, null,"\/p\/xsb\/src\/1564\/tree\/\/trunk\/XSB\/docs\/userman\/library.tex?__cf_chl_rt_tk=kb6_fKtk97bzuAaYqQ6BvVxn22.0r32x21YuYN4XJ.M-1752330921-1.0.1.1-MyD4r5mpiR80eDJQgC8uOXzYIRJYUWm9Yx0t26yg2Gk"+ window._cf_chl_opt.cOgUHash);a.onload = function() {history.replaceState(null, null, ogU);}}document.getElementsByTagName('head')[0].appendChild(a);}());</script></body></html>